J-code units from a dose

**My Thought Process for Calculating Billing Units for J1745**

Alright, so the core task here is to figure out how many billing units I need to report for the drug represented by HCPCS code J1745, specifically accounting for both what was administered to the patient and what was ultimately wasted.

The HCPCS descriptor for J1745 is key: "injection, infliximab, 10 mg." This tells me that each "unit" for billing purposes corresponds to 10 mg of infliximab.

Now, I have the patient's weight, which is 78 kg, and the prescribed dose is 5 mg per kilogram. My first calculation is to determine the total milligrams (mg) that were actually administered. That's a straightforward multiplication: 78 kg * 5 mg/kg = 390 mg. This is the amount that went into the patient.

The pharmacy prepared the medication by reconstituting four single-dose vials, each containing 100 mg. So, the total amount prepared was 4 * 100 mg = 400 mg.

Since 390 mg was administered and 400 mg was prepared, the difference, 400 mg - 390 mg, represents the wasted amount, which is 10 mg.

Now, to translate these milligrams into billing units, I need to use the descriptor dosage of 10 mg.

For the **administered units**, I take the total administered dose (390 mg) and divide it by the descriptor dosage (10 mg): 390 mg / 10 mg = 39 units.

For the **wasted units**, I take the wasted dose (10 mg) and divide it by the descriptor dosage (10 mg): 10 mg / 10 mg = 1 unit. The guideline explicitly states that wastage from a single-dose vial is reported separately and not included in the administered units, which aligns perfectly with this calculation.

I'm going to perform a quick sanity check based on the provided rule: "A HCPCS Level II drug code carries a dosage in its descriptor. Billing units are the administered dose divided by the descriptor dosage. A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units."

My calculations of 39 administered units (390 mg / 10 mg) and 1 wasted unit (10 mg / 10 mg) both result in whole numbers, so I don't need to worry about rounding up for partial units in this specific scenario. The wastage is correctly separated.

Finally, I need to output this in the requested JSON format:
```json
{
  "units_administered": 39,
  "units_wasted": 1
}
```
Everything appears consistent and accurate according to the provided information and rules.

**My Thought Process for Infliximab (J1745) Billing Unit Calculation**

Alright, let's break down this infliximab scenario. My primary goal here is to accurately determine the billing units for both the administered dose and any wastage, adhering to standard HCPCS coding principles, especially for single-dose vials.

First, I've got the core details: the HCPCS code is J1745, which represents Infliximab at a descriptor dosage of 10 mg. The member's weight is 78 kg, and the prescribed dosage is 5 mg/kg.

My initial calculation for the administered dose is straightforward: 78 kg multiplied by 5 mg/kg equals 390 mg. This is the actual amount of infliximab that went into the patient.

Now, I need to consider how this translates into billing units for J1745. The rule states that billing units are derived by dividing the administered dose by the descriptor dosage. So, 390 mg divided by 10 mg per unit gives me exactly 39 units. I also need to keep in mind the rule about partial units being rounded up – thankfully, in this case, the division results in a whole number, so no rounding up is necessary for the administered units.

Next, I look at the pharmacy's actions. They reconstituted four 100 mg single-dose vials, totaling 400 mg. Since the administered dose was 390 mg, there was 10 mg of the drug left over – this is the wastage.

Crucially, I recall that wastage from a single-dose vial is reported separately. So, I need to calculate billing units for this 10 mg of wasted medication. Again, I divide the wasted amount by the descriptor dosage: 10 mg divided by 10 mg per unit equals 1 unit. This is also an exact calculation, so no rounding is needed here either.

To confirm my understanding, I'm mentally reviewing the governing rules: "HCPCS billing units are the administered dose divided by the descriptor dosage." "A partial unit is billed as a whole unit." And most importantly for this scenario, "wastage from a single-dose vial is reported separately and is not included in the administered units."

So, my calculated units are:
*   **Units Administered:** 39 (390 mg / 10 mg/unit)
*   **Units Wasted:** 1 (10 mg / 10 mg/unit)

Just to be absolutely sure, I'm doing a quick sanity check. If the administered dose had been, say, 385 mg, the administered units would have been 39 (38.5 rounded up). If the wasted dose had been 5 mg, the wasted units would have been 1 (0.5 rounded up). This reinforces my understanding of the rounding rule for partial units, though it doesn't apply to this specific scenario's exact divisions.

Finally, I check if the total units account for the total drug prepared. 39 administered units + 1 wasted unit = 40 units. Since each unit is 10 mg, this accounts for 400 mg of drug, which precisely matches the four 100 mg vials that were reconstituted. This confirms that my calculations align with the total volume of the drug handled.

Therefore, the final billing units are:
*   `units_administered`: 39
*   `units_wasted`: 1

Let me work through this step by step.

The member weighs 78 kg and receives infliximab at 5 mg/kg.
Total dose = 78 kg × 5 mg/kg = 390 mg

The problem states that 390 mg is administered and the remainder is discarded.

The pharmacy reconstitutes four 100 mg single-dose vials = 400 mg total available.

390 mg administered, 10 mg discarded (wasted).

Now for billing units:
HCPCS code J1745 — injection, infliximab, 10 mg

The descriptor dosage is 10 mg per unit.

Units administered = administered dose / descriptor dosage = 390 mg / 10 mg = 39 units

Units wasted = wasted dose / descriptor dosage = 10 mg / 10 mg = 1 unit

Both are whole numbers, so no rounding needed.

Let me double-check the rules:
- "Billing units are the administered dose divided by the descriptor dosage."
- "A partial unit is billed as a whole unit" — not applicable here since both are whole.
- "wastage from a single-dose vial is reported separately and is not included in the administered units" — so the wasted amount is reported separately as units_wasted, not included in units_administered.

units_administered = 390 / 10 = 39
units_wasted = 10 / 10 = 1

Both check out.

The member weighs 78 kg and receives infliximab 5 mg/kg.
Total dose ordered = 78 kg * 5 mg/kg = 390 mg.
The pharmacy reconstitutes four 100 mg single-dose vials = 400 mg total.
Administered = 390 mg.
Discarded (wasted) = 400 mg - 390 mg = 10 mg.

HCPCS code J1745 descriptor: injection, infliximab, 10 mg.
Billing units = administered dose / descriptor dosage.
Administered units = 390 mg / 10 mg = 39 units.
Wasted units = 10 mg / 10 mg = 1 unit.

Wait, the prompt says: "A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units."
Administered dose = 390 mg. 390 / 10 = 39.
Wasted dose = 10 mg. 10 / 10 = 1.

Let's double check.
Weight = 78 kg
Dose = 5 mg/kg
Total dose = 390 mg
Vials = 4 * 100 mg = 400 mg
Administered = 390 mg
Wasted = 10 mg

J1745 = 10 mg per unit.
units_administered = 390 / 10 = 39
units_wasted = 10 / 10 = 1

Are there any partial units? No, 390 and 10 are both exact multiples of 10.
So units_administered = 39
units_wasted = 1

Let me review the required keys:
"units_administered" (integer billing units for the administered drug)
"units_wasted" (integer billing units of discarded drug)

Values:
units_administered: 39
units_wasted: 1

Check the math again:
78 * 5 = 390.
4 vials * 100 mg = 400 mg.
400 - 390 = 10 mg wasted.
390 / 10 = 39 units.
10 / 10 = 1 unit.

Everything is correct.
Output JSON format:
```json
{
  "units_administered": 39,
  "units_wasted": 1
}
```
No other text.
Done.

Let me work through this step by step.

1. Calculate the dose ordered:
   - Member weight: 78 kg
   - Dose: 5 mg/kg
   - Total dose ordered: 78 × 5 = 390 mg

2. Determine the HCPCS code and descriptor:
   - J1745 — injection, infliximab, 10 mg
   - So each billing unit = 10 mg

3. Vials reconstituted:
   - Four 100 mg single-dose vials = 400 mg total available

4. Administered:
   - 390 mg administered
   - Billing units for administered drug = 390 mg ÷ 10 mg/unit = 39 units
   - This is exact, so 39 units.

5. Wasted:
   - Total available: 400 mg
   - Administered: 390 mg
   - Discarded: 400 - 390 = 10 mg
   - Billing units for wasted drug = 10 mg ÷ 10 mg/unit = 1 unit

6. Check the rules:
   - "A partial unit is billed as a whole unit" — 390/10 = 39 exactly, no partial unit. 10/10 = 1 exactly.
   - "wastage from a single-dose vial is reported separately and is not included in the administered units" — correct, we separated them.

So:
- units_administered: 39
- units_wasted: 1

The member weighs 78 kg and receives infliximab 5 mg/kg.
Total dose ordered = 78 kg * 5 mg/kg = 390 mg.
The pharmacy reconstitutes four 100 mg single-dose vials = 400 mg total.
Administered = 390 mg.
Discarded (wasted) = 400 mg - 390 mg = 10 mg.

HCPCS code J1745 descriptor: injection, infliximab, 10 mg.
Billing units = administered dose / descriptor dosage.
Administered dose = 390 mg.
Descriptor dosage = 10 mg.
Units administered = 390 / 10 = 39.

Wastage from a single-dose vial is reported separately.
Wasted dose = 10 mg.
Units wasted = 10 / 10 = 1.

Let's double check.
Weight = 78 kg
Dose = 5 mg/kg -> 390 mg
Vials = 4 x 100 mg = 400 mg
Administered = 390 mg
Wasted = 10 mg

J1745 is 10 mg per unit.
Administered units = 390 / 10 = 39
Wasted units = 10 / 10 = 1

Are there any partial units? 390 / 10 = 39 exactly. 10 / 10 = 1 exactly.
So units_administered = 39
units_wasted = 1

Required keys: "units_administered" (integer), "units_wasted" (integer).
Output JSON format.
```json
{
  "units_administered": 39,
  "units_wasted": 1
}
```
Wait, let me reread the prompt carefully.
"A member weighing 78 kg receives infliximab 5 mg/kg. The pharmacy reconstitutes four 100 mg single-dose vials and 390 mg is administered; the remainder is discarded."
"Descriptor for this exercise: J1745 — injection, infliximab, 10 mg."
"HCPCS DRUG BILLING UNITS
A HCPCS Level II drug code carries a dosage in its descriptor. Billing units are
the administered dose divided by the descriptor dosage. A partial unit is billed
as a whole unit; wastage from a single-dose vial is reported separately and is
not included in the administered units."

Calculations:
Administered = 390 mg. 390 / 10 = 39 units.
Wasted = 400 - 390 = 10 mg. 10 / 10 = 1 unit.

Everything is straightforward.
No rounding needed since they are exact integers.
Result:
units_administered: 39
units_wasted: 1
I will output the JSON block.

We need answer a task. Need output exactly one fenced JSON code block. Required keys: "units_administered" (integer billing units for the administered drug) and "units_wasted" (integer billing units of discarded drug). Need compute HCPCS J1745 injection, infliximab, 10 mg. Billing units are administered dose divided by descriptor dosage (10 mg). Partial unit billed as whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units. Descriptor dosage 10 mg. Administered dose = 390 mg. Units administered = 390 / 10 = 39 exactly. Is it a partial? No, exactly 39, so integer 39. Wait maybe weight 78 kg at 5 mg/kg = 390 mg indeed. The pharmacy reconstitutes four 100 mg single-dose vials = 400 mg total. Administered 390 mg; remainder discarded = 10 mg. Wastage from single-dose vials: discarded drug = 10 mg. Billing units of discarded drug = 10 mg / 10 mg = 1 unit. Need verify: "Wastage from a single-dose vial is reported separately and is not included in the administered units." So units_wasted = integer billing units of discarded drug. Since discarded remainder is 10 mg, divided by 10 mg = 1. But careful: They used four 100 mg single-dose vials. Each vial is single-dose. The administered dose is 390 mg. How many vials used? Since each vial is 100 mg single-dose, to get 390 mg, they'd need 4 vials, with 10 mg discarded. But wait "reconstitutes four 100 mg single-dose vials and 390 mg is administered; the remainder is discarded." They reconstituted four vials, total 400 mg, administered 390, remainder 10 mg discarded. So wastage = 10 mg. Billing units for discarded drug: descriptor dosage 10 mg, partial unit billed as whole unit. 10mg/10mg = 1 unit. If remainder were less than 10 mg, partial unit would bill as 1 unit (since partial unit billed as whole unit). But here exactly 1.

Need think if there's any nuance about billing units for administered drug: dose divided by descriptor dosage, round up? It says "Billing units are the administered dose divided by the descriptor dosage. A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units." So if administered dose / dosage is not integer, round up to next whole unit. Here 390/10=39 exactly, no partial. So units_administered = 39. units_wasted = 10/10 = 1. But is wastage also subject to partial unit rule? It says "wastage from a single-dose vial is reported separately". The rules: "A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units." This partial unit rule applies to billing units generally: "Billing units are the administered dose divided by the descriptor dosage. A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units." So for wastage, billing units are discarded dose divided by descriptor dosage? It says "units_wasted (integer billing units of discarded drug)". So yes discarded drug amount = total in vial(s) minus administered? Need careful: They reconstituted four 100 mg single-dose vials. Administered 390 mg. Remainder discarded = 10 mg. "wastage from a single-dose vial" - they opened four single-dose vials. Normally, if you have single-dose vials, any leftover in each vial after drawing the needed amount may be discarded. They used four vials, but did they use full 100 mg from three vials and 90 mg from the fourth? Let's see: To administer 390 mg, you'd withdraw 100 mg from vial 1, 100 from vial 2, 100 from vial 3, and 90 from vial 4. The remainder in vial 4 is 10 mg, which is discarded. But what about the other three vials? If you withdraw entire 100 mg from each of the first three, there is no remainder in those vials. The fourth vial had 100 mg, you withdraw 90 mg, leaving 10 mg discarded. So total discarded = 10 mg. Yes.

But wait, is there any overfill or something? Not mentioned. So 10 mg. Billing units of discarded drug = 10mg / 10mg = 1. But maybe since it's a single-dose vial, the entire remaining contents of the vial(s) are discarded. They used four vials, but only one vial has remainder 10 mg, the rest empty. So discarded = 10 mg => 1 unit.

However, there is a known HCPCS J1745 billing unit: J1745 is injection, infliximab, 10 mg. For infused drugs, billing units = number of 10 mg increments, rounding up? Actually Medicare: For J1745, bill 1 unit per 10 mg. If 390 mg administered, bill 39 units. Wastage: If a single-dose vial, wastage is billed with JW modifier, and units are the amount discarded in multiples of 10 mg, rounded up? Let's think: Descriptor dosage 10 mg. Billing units are administered dose divided by dosage, partial billed as whole unit. For wastage, you also divide discarded amount by 10 mg? The discarded amount is 10 mg, so 1 unit. If it were 5 mg discarded, it would be a partial unit (0.5) and billed as a whole unit (1). Here it's exactly 10 mg, so 1.

Wait, the weight/dose: 78 kg * 5 mg/kg = 390 mg. Yes. Four 100 mg vials = 400 mg. Discarded = 10 mg. So 390 mg administered, 10 mg discarded. But is there an issue that they reconstituted four vials, meaning they mixed 4 vials to get 400 mg, and then administered 390 mg. In reality, if you reconstitute four vials into a single infusion bag, the entire 400 mg is in the bag. You administer 390 mg, and 10 mg remains in the bag and is discarded. So discarded = 10 mg. Same.

Need output JSON:
{
  "units_administered": 39,
  "units_wasted": 1
}

But let's confirm no trick with "partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units." Could units_administered be calculated from the dose based on weight? The dose is 5 mg/kg for 78 kg = 390 mg. But sometimes infliximab dosing is rounded to nearest vial? No, "390 mg is administered". So use actual administered 390 mg. Administered units = 390 / 10 = 39.

Check integer requirement: "units_administered" (integer billing units...), "units_wasted" (integer...). So output JSON numbers: 39 and 1.

Do we need to include any other keys? Required keys are exactly those two. Do not add keys. Output exactly one fenced JSON code block and nothing else. So:

```json
{
  "units_administered": 39,
  "units_wasted": 1
}
```

Wait, before finalizing, let's re-read the reference carefully:

REFERENCE MATERIAL FOR THIS ITEM

HCPCS DRUG BILLING UNITS
A HCPCS Level II drug code carries a dosage in its descriptor. Billing units are
the administered dose divided by the descriptor dosage. A partial unit is billed
as a whole unit; wastage from a single-dose vial is reported separately and is
not included in the administered units.
Descriptor for this exercise: J1745 — injection, infliximab, 10 mg.

So:
- Administered dose = 390 mg.
- Descriptor dosage = 10 mg.
Billing units (administered) = 390 / 10 = 39. Since it's exact, no partial. units_administered = 39.

Wastage:
- The pharmacy reconstitutes four 100 mg single-dose vials = total 400 mg.
- Administered 390 mg; remainder discarded = 10 mg.
- "wastage from a single-dose vial is reported separately and is not included in the administered units." So we calculate billing units of discarded drug: discarded dose divided by descriptor dosage? It says "Billing units are the administered dose divided by the descriptor dosage." Then partial unit rule. Then wastage reported separately. It doesn't explicitly say "discarded dose divided by descriptor dosage", but the task asks for "integer billing units of discarded drug". By analogy and HCPCS rules, you divide discarded amount (10 mg) by 10 mg = 1 unit. Since partial unit billed as whole unit, if there were, say, 5 mg discarded, units_wasted would be 1. Here 10 mg gives 1.

But consider: They used four 100 mg single-dose vials. If they used partial amounts from multiple vials, perhaps the discarded amount is the sum of remainders from each vial. Four vials, to get 390 mg: 100+100+100+90. Remainder: 0+0+0+10 = 10 mg. Yes.

What if they administered 390 mg, but the dose prepared from four vials means the vials are single-dose, so any unused portion from each vial is discarded. They used 4 vials. Vials 1-3: used 100 mg each, no discard. Vial 4: used 90 mg, discard 10 mg. Total discard 10 mg. Same.

But wait, some billing rules say that for a single-dose vial, if you use any amount from the vial, the rest of that vial is wastage, and the wastage units are the full remaining amount in the vial(s), which is 10 mg. However, is the wastage calculated as the number of full vials minus the vials' contents used? Actually, if vials are 100 mg each, and you need 390 mg, you open 4 vials. The total drug in the 4 vials is 400 mg. You administer 390 mg. The amount discarded is 10 mg, which is less than a full vial. Since it's a single-dose vial, you can't save it. So yes, 10 mg discarded.

Now, the billing units of discarded drug: If the discarded amount is 10 mg, divided by 10 mg = 1. If the discarded amount had been, say, 5 mg, billing units would be 1 (partial unit billed as whole unit). Since it's exactly 10 mg, it's 1. Good.

Let's consider if the administered units should be rounded up from the number of vials? No, "administered dose divided by descriptor dosage". The administered dose is explicitly 390 mg (and derived from 78*5). So 39.

Double-check arithmetic: 78 kg * 5 mg/kg = 390 mg. Yes. 390 / 10 = 39. Four vials * 100 mg = 400 mg. 400 - 390 = 10 mg discarded. 10 / 10 = 1. units_wasted = 1.

Are there any edge cases? "A partial unit is billed as a whole unit" - If 390/10 = 39.0, no round needed. If they considered the administered dose as 78 * 5 = 390. Yes.

Wait, infliximab dosing: sometimes it's 5 mg/kg, for 78 kg that's 390 mg. They may round to vial size? But the prompt says "390 mg is administered". So no rounding to 400 mg.

Could units_wasted be 0? Because the remainder discarded is 10 mg, which is exactly 1 unit. So not zero.

Could the remainder be 400 - 390 = 10 mg, but because it's from a single-dose vial, the wastage is reported separately, and maybe the entire fourth vial is considered wasted? No, because 90 mg was administered from it. Only 10 mg remains. So only 10 mg is wasted/discarded. If you had to discard the whole vial because it's single-dose and you only used 90 mg, that means you discard 10 mg, not 100 mg. The 90 mg is administered. So the "discarded drug" is the 10 mg left over.

Could there be an interpretation that they reconstituted four vials, meaning they mixed all 400 mg, and then "390 mg is administered; the remainder is discarded." The remainder is 10 mg. Yes.

Thus final answer is straightforward.

Wait, let's re-read: "The pharmacy reconstitutes four 100 mg single-dose vials and 390 mg is administered; the remainder is discarded." "Reconstitutes four 100 mg single-dose vials" - If they reconstitute (i.e., add diluent and withdraw) four vials, they now have four vials' worth of solution. They administer 390 mg. The remainder is 10 mg. If they had used three full vials (300 mg) and 90 mg from the fourth, the remainder in the fourth is 10 mg. So 390 mg administered, 10 mg remainder. Yes.

Let's ensure output format: exactly one fenced JSON code block. No commentary. Use JSON null? Not needed. The keys required: "units_administered" and "units_wasted". Both integers.

```json
{
  "units_administered": 39,
  "units_wasted": 1
}
```

Check if values should be quoted? The task says: "Required keys: "units_administered" (integer billing units for the administered drug) and "units_wasted" (integer billing units of discarded drug)." In the OUTPUT CONTRACT: "Integers are JSON numbers with no units and no quotes." So they must be numbers, not strings. So 39 and 1, not "39".

One more nuance: "Report codes exactly as they are written... Where a code carries a seventh character, include it." This is about codes, not relevant here since we output integers.

"Booleans are JSON true and false, not the strings..." Not relevant.

"Where an item supplies reference material, that material is authoritative... Never invent a code. If you cannot identify the correct value, return the string "UNKNOWN" for that key." We identified correct values.

Everything good.

Wait, I should check the phrase: "wastage from a single-dose vial is reported separately and is not included in the administered units." Does this mean that wastage is not rounded up? It says "A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units." The semicolon separates two clauses. The first clause: "A partial unit is billed as a whole unit;" This applies to billing units generally. The second: "wastage from a single-dose vial is reported separately and is not included in the administered units." So for wastage, you report it separately, and you also apply the same billing unit methodology (divide by descriptor dosage, round up partial). So 10 mg -> 1 unit. If it were 5 mg, round up to 1 unit. Since it's 10 mg, it's exactly 1.

Let's test an alternative: Some might think that because four vials were used, the wastage is 4 vials * 100 mg - 390 mg = 10 mg. So 1 unit. Yes.

Is there any possibility that units_administered should be 40? Because they had to use 4 vials (400 mg), and the dose administered is 390, but the billing is based on the amount drawn up? No, "Billing units are the administered dose divided by the descriptor dosage." Administered dose is 390 mg, not 400. So 39. The fact they reconstituted 400 mg doesn't change administered dose. So 39. If they had administered 400 mg, it would be 40.

What about the member's weight? 78 kg * 5 mg/kg = 390 mg. It matches the stated administered amount. No issue.

Thus final answer.

One last check: The JSON must be in a fenced code block. Exactly one. So:

```json
{
  "units_administered": 39,
  "units_wasted": 1
}
```

No other text. Done.

We need answer one fenced JSON block with required keys: "units_administered" and "units_wasted". Need compute billing units for HCPCS J1745 injection, infliximab, 10 mg. Descriptor dosage: 10 mg. Billing units = administered dose divided by descriptor dosage. A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and not included in administered units.

We have: member weighing 78 kg receives infliximab 5 mg/kg. Dose ordered? It says receives infliximab 5 mg/kg. The pharmacy reconstitutes four 100 mg single-dose vials and 390 mg is administered; the remainder is discarded.

Need compute administered dose: 78 kg * 5 mg/kg = 390 mg. Yes, 78*5=390. Administered = 390 mg. Descriptor dosage 10 mg. Billing units for administered drug = 390 / 10 = 39 units exactly. Wait descriptor "injection, infliximab, 10 mg" means each unit is 10 mg. 390/10=39 exactly, integer billing units = 39.

Now wastage: pharmacy reconstitutes four 100 mg single-dose vials. Total prepared = 4 * 100 = 400 mg. Administered = 390 mg. Remainder discarded = 10 mg. Wastage from a single-dose vial is reported separately and is not included in the administered units. Need integer billing units of discarded drug. Wastage is 10 mg discarded. Descriptor dosage 10 mg per unit. Billing units for wastage = 10 / 10 = 1 unit. Wait: The remainder is 10 mg from single-dose vials. It says "reconstitutes four 100 mg single-dose vials and 390 mg is administered; the remainder is discarded." Total 400 mg, administered 390 mg, discarded 10 mg. Wastage billing units = discarded dose / descriptor dosage. Discarded 10 mg / 10 mg = 1 unit. Partial unit? It's exactly 1. If remainder had been less than 10 mg, a partial unit is billed as a whole unit? Rule: "A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units." This likely applies to both administered and wasted? Billing units = administered dose divided by descriptor dosage. A partial unit is billed as a whole unit. For wastage, it's the discarded amount divided by descriptor dosage; if partial, round up? The rule says "A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units." It says "Billing units are the administered dose divided by the descriptor dosage. A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units." It defines billing units as administered dose divided by descriptor dosage, and partial unit billed whole. Then wastage is separate. It doesn't explicitly say how to compute wastage units, but by analogy wastage is discarded dose divided by descriptor dosage, and partial unit is billed as whole unit? Usually HCPCS drug billing: For wastage, you bill the amount discarded in units, with each unit = descriptor dosage, and any partial unit discarded is billed as a whole unit? Let's recall real-world: For J codes, billing units are based on the amount administered, using the dosage in the descriptor; e.g., J1745 is 10 mg, so administer 390 mg = 39 units. If there is wastage from single-dose vial, bill the discarded amount also in units, e.g., discard 10 mg = 1 unit. If discard 5 mg, bill 1 unit (since partial units billed as whole). But here discard is exactly 10 mg, which is 1 unit. No rounding issue.

Need ensure administered units integer: 39. Wasted units integer: 1.

Wait, let's double-check the scenario. It says "The pharmacy reconstitutes four 100 mg single-dose vials and 390 mg is administered; the remainder is discarded." Four vials of 100 mg each: total 400 mg. Administered 390 mg. Remainder 10 mg. Yes.

But could there be a nuance: The member receives infliximab 5 mg/kg. Weight 78 kg. Dose = 390 mg. Pharmacy reconstitutes four 100 mg single-dose vials = 400 mg. Administered 390 mg. Discarded 10 mg. Billing units administered = 39. Wasted = 1. That seems straightforward.

But wait, the descriptor: "J1745 — injection, infliximab, 10 mg." The billing units are administered dose divided by descriptor dosage. If the code descriptor dosage is 10 mg, billing unit = 10 mg. Administered dose 390 mg / 10 mg per unit = 39 units. Wastage: 10 mg / 10 mg per unit = 1 unit. Both integers.

Let's verify no need to consider that the vials are 100 mg each, and maybe the remainder from each vial? "reconstitutes four 100 mg single-dose vials" means they prepared four separate single-dose vials? Actually infliximab is a powder in single-dose vial, each vial contains 100 mg. They reconstitute four vials to get 400 mg total, draw up 390 mg into a syringe, and discard 10 mg. Since each vial is single-dose, maybe each vial is 100 mg, they use all four? Let's see: four 100 mg vials = 400 mg. To administer 390 mg, they might draw from the vials; if they use 4 vials, maybe they use 3 full vials (300 mg) plus 90 mg from the fourth vial, discarding 10 mg from that fourth vial. Since the fourth vial is single-dose, the remaining 10 mg in that vial is wasted. The first three vials were fully used? Actually each vial is 100 mg. If they administer 390 mg, they need the contents of four vials? Wait 3 vials give 300 mg. Need 90 mg more, so they open a fourth vial, withdraw 90 mg, and the remaining 10 mg in the fourth vial is discarded because it's a single-dose vial and cannot be saved? Or they reconstitute four vials, pool them? But if it's single-dose vials, you cannot pool and store? Let's think: Infliximab vials: each single-dose vial contains 100 mg. To prepare a 390 mg dose, the pharmacy would need to use 4 vials: three full vials (300 mg) plus one vial from which 90 mg is withdrawn, leaving 10 mg in that vial that is discarded as waste. So total drug into the dose is 390 mg, total discarded is 10 mg from the fourth vial. They "reconstitute four 100 mg single-dose vials" total 400 mg. Administer 390 mg, discard remainder (10 mg). Yes.

Wastage billing: Usually for single-dose vial wastage, you report the amount discarded using the JW modifier, billed in units. The amount discarded is 10 mg = 1 unit. There is no partial unit issue because exactly 10 mg.

Thus JSON:
{
  "units_administered": 39,
  "units_wasted": 1
}

Wait, check if they want integer billing units for administered drug and integer billing units of discarded drug. Yes. units_administered integer = 39. units_wasted integer = 1.

But let's consider if the administered dose is based on 5 mg/kg of 78 kg = 390 mg. The reference says: "A member weighing 78 kg receives infliximab 5 mg/kg." That is 390 mg ordered/administered. It says "and 390 mg is administered". So administered = 390 mg. Good.

What about the weight? 78 kg * 5 = 390. Yes.

Now, is there any possibility that billing units for administered should be 40? Because "A partial unit is billed as a whole unit" and the administered dose divided by descriptor dosage: If administered dose were, say, 395 mg, 395/10=39.5 -> 40 units. But here 390/10=39.0 exactly, so 39. No rounding up needed.

Wastage: remainder = 400 - 390 = 10 mg. 10/10 = 1.0, so 1 unit. If remainder were 5 mg, would be 0.5 -> 1 unit. But it's 10 mg.

Wait, total prepared: four 100 mg single-dose vials. Actually reconstituting four vials yields 4 * 100 = 400 mg. If 390 mg administered, remainder 10 mg. Yes.

Let's make sure the JSON keys exactly: "units_administered" and "units_wasted". Values must be JSON numbers (integers). Output exactly one fenced JSON code block and nothing else. No preamble, no commentary. Use ```json ... ```. Ensure no trailing commas.

Let's draft final:

```json
{
  "units_administered": 39,
  "units_wasted": 1
}
```

Check: The task requires "Required keys: "units_administered" (integer billing units for the administered drug) and "units_wasted" (integer billing units of discarded drug)." Yes.

One more thought: The descriptor: "J1745 — injection, infliximab, 10 mg." The billing units are administered dose divided by descriptor dosage. A partial unit is billed as a whole unit. Is the discarded drug also divided by descriptor dosage and rounded up? The remainder is 10 mg, which is exactly 1 unit. So answer stands.

But wait: Let's re-read: "The pharmacy reconstitutes four 100 mg single-dose vials and 390 mg is administered; the remainder is discarded." Does "the remainder is discarded" mean the remainder of the 390 mg dose? No, remainder of the reconstituted drug. Total 400 mg, 390 mg administered, 10 mg discarded. Good.

Could there be an issue: "receives infliximab 5 mg/kg" means the dose is 5 mg per kg. 78 kg * 5 = 390 mg. They administered 390 mg. Good.

I think done.

We need answer JSON only. Need solve task.

We have reference: HCPCS J1745 injection, infliximab, 10 mg. Billing units = administered dose divided by descriptor dosage. Partial unit billed as whole unit; wastage from single-dose vial reported separately and not included in administered units.

Member weight 78 kg receives infliximab 5 mg/kg. Pharmacy reconstitutes four 100 mg single-dose vials and 390 mg is administered; remainder discarded.

Need units_administered (integer billing units for administered drug) and units_wasted (integer billing units of discarded drug).

We need calculate administered dose? They say member receives infliximab 5 mg/kg, weight 78 kg => 78 * 5 = 390 mg. Indeed administered is 390 mg. Descriptor dosage J1745 = 10 mg. Billing units administered = administered dose / descriptor dosage = 390 / 10 = 39 units. Partial unit whole? 39 exactly no partial. So administered units = 39.

Now wastage: They reconstitute four 100 mg single-dose vials. Total drug prepared = 4 * 100 mg = 400 mg. Administered 390 mg. Remainder discarded = 400 - 390 = 10 mg. Is that correct? They reconstitute four 100 mg single-dose vials and 390 mg is administered; remainder is discarded. Total volume 400 mg. Discarded amount = 10 mg. Wastage billing units = discarded drug divided by descriptor dosage = 10 / 10 = 1 unit. Partial unit? 1 exactly. So units_wasted = 1.

But we must carefully interpret HCPCS drug billing units. "Billing units are the administered dose divided by the descriptor dosage. A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units." For discarded drug, how to compute units? It says "wastage from a single-dose vial is reported separately" and "units_wasted (integer billing units of discarded drug)." So wastage units = discarded dose / descriptor dosage, with partial units rounded up? Let's parse: "Billing units are the administered dose divided by the descriptor dosage. A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units." The rule for billing units: administered dose divided by descriptor dosage. Then partial unit is billed as whole unit. That applies to billing units in general. For wastage, it's discarded drug units. Discarded drug = 10 mg, divided by 10 mg = 1 unit exactly. No rounding issue.

But wait: Could wastage be from four 100 mg vials, each single-dose, remainder discarded. They reconstituted four vials => total 400 mg. Administered 390. Discarded 10 mg. However, is there any concept that each vial's wastage is reported per vial with partial units rounded up? For single-dose vials, if you have four vials of 100 mg, you might draw 390 mg from them. How much is discarded? If you use four 100 mg vials, you use 390 mg total, leaving 10 mg total across vials (maybe one vial has 10 mg remaining, others empty). Wastage billing units are total discarded drug / dosage. So 1 unit. But HCPCS J1745 billing for wastage: Some payers require reporting wastage in units where 1 unit = 10 mg. If 10 mg discarded, that's 1 unit. Right.

But let's ensure no nuance: "The pharmacy reconstitutes four 100 mg single-dose vials and 390 mg is administered; the remainder is discarded." Wait, "reconstitutes four 100 mg single-dose vials". Infliximab 100 mg vial: after reconstitution, maybe each vial contains 100 mg? Usually infliximab is 100 mg vial. Four vials total 400 mg. Administer 390 mg. Discard remainder = 10 mg. Yes.

Let's check math: Dose ordered 5 mg/kg * 78 kg = 390 mg. Administered = 390 mg. Units administered = ceil(390/10)? 390/10 = 39.0. Ceil = 39. Good.

Wastage: total available 400 mg, administered 390 mg, discarded 10 mg. Units wasted = ceil(10/10)? = 1. Good.

But wait, is there possible alternate interpretation: They reconstituted four 100 mg single-dose vials, but perhaps 390 mg administered means 3.9 vials used, and one full 100 mg vial plus remainder? No: four vials = 400 mg. If 390 mg administered, remainder discarded is 10 mg. However, because each vial is single-dose, once reconstituted, each vial's entire contents must be used or discarded? Actually single-dose vial: after reconstitution, the vial is single-use; any remainder in each vial after drawing a dose is discarded. But the total amount discarded might be more than 10 mg if you have to discard partial vials? Let's think: You have four separate 100 mg vials. To administer 390 mg, you could draw 100 mg from vial 1, 100 from vial 2, 100 from vial 3, and 90 mg from vial 4. Then vial 4 had 100 mg, you drew 90 mg, leaving 10 mg in vial 4 to discard. Vials 1-3 are empty (maybe residual negligible). So total discarded = 10 mg. That's consistent.

But if you had to use full vials? No, you can withdraw partial from a vial. The remainder in that vial is discarded. So total discarded = 10 mg. Good.

Could there be an argument that because it's "single-dose vial", you cannot use a vial for more than one patient, but you can draw partial. Wastage is amount remaining in vial(s) after drawing the administered amount. Yes.

Check rounding rule: "Round half up to the cent at the end of a calculation, not at each intermediate step." But this task is integer units, not money. For units, "A partial unit is billed as a whole unit" meaning always round up to next whole unit (ceiling), regardless of fraction. For 390/10=39 exactly, no partial. For 10/10=1 exactly.

But wait, is the dose 5 mg/kg for a 78 kg member = 390 mg. Correct. Could administered dose be rounded? No.

Potential twist: HCPCS J1745 descriptor: "injection, infliximab, 10 mg". Actually real HCPCS J1745 is "Injection, infliximab, 10 mg" (and includes biosimilars?). Billing unit = 10 mg. Yes. Administered 390 mg = 39 units. Wastage: For drugs, billing for wastage is often reported with JW modifier for discarded drug. The units for wastage are based on the amount discarded, also in multiples of the billing unit (10 mg). If 10 mg discarded, 1 unit. Some instructions: "the billing units for wastage should be reported separately and calculated by dividing the amount of discarded drug by the dosage in the descriptor, rounding up to the nearest whole unit." So 10/10 = 1. Good.

Need output exactly one fenced JSON code block. Required keys: "units_administered" integer, "units_wasted" integer. Use JSON numbers no quotes. So:

```json
{
  "units_administered": 39,
  "units_wasted": 1
}
```

Wait, are we sure "units_wasted" is based on discarded drug or based on the number of vials? The key: "units_wasted" (integer billing units of discarded drug). Discarded drug = remainder = 400 - 390 = 10 mg. Billing units of discarded drug = 10 mg / 10 mg per unit = 1. Yes.

Let's consider if there's any nuance about "four 100 mg single-dose vials". If each vial after reconstitution might not be exactly 100 mg? The descriptor is 100 mg per vial. They say "four 100 mg single-dose vials". So total 400 mg. Administered 390 mg. Remainder discarded = 10 mg. Yes.

What about "partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units." The phrase "A partial unit is billed as a whole unit" could refer to the result of the division. If division yields e.g., 1.1 units, bill 2. Here 39 and 1 exact.

Double-check weight dose: 78 kg * 5 mg/kg = 390 mg. Yes.

One more thought: The administered dose is 390 mg, but total prepared is 400 mg. Did they administer from four vials? They reconstituted four 100 mg vials. If each is single-dose, maybe you cannot combine vials? Actually you can combine reconstituted vials into an IV bag for infusion. Infliximab is IV infusion. The pharmacy reconstitutes four vials and adds to IV bag. The total drug in bag is 400 mg. Administer 390 mg? Infusion pumps might administer the full bag? But the prompt says "390 mg is administered; the remainder is discarded." So they intentionally administered 390 mg, leaving 10 mg in the bag discarded. Or maybe the bag has 400 mg, dose is 390 mg, they stop infusion after 390 mg and discard 10 mg. Yes.

But if the dose is 5 mg/kg * 78 = 390 mg, why prepare 400 mg? Because vials are 100 mg, need at least 390 mg, so use four vials (400 mg). Administer 390 mg, waste 10 mg. Exactly.

Thus answer.

Need to ensure formatting: fenced code block with json. Nothing else. No preamble. Use exactly:

```json
{
  "units_administered": 39,
  "units_wasted": 1
}
```

Check if key names exactly as required: "units_administered" and "units_wasted". Yes.

Should I include trailing newline? It's fine. Just the code block.

Let's also consider if they expect 40 administered? Wait, "billing units are the administered dose divided by the descriptor dosage. A partial unit is billed as a whole unit". Administered dose = 390 mg. 390/10 = 39. Not partial. So 39.

Some might think: dose 5 mg/kg maybe round weight? No.

Check if wastage should be rounded per vial: If you have four vials, one vial had 10 mg left, that's 1 unit. If you had drawn 90 mg from the fourth vial, maybe you actually discard 90? No, you drew 90 mg into the infusion, leaving 10 mg in vial. Wait, let's simulate: Need 390 mg total. Use vial A: draw 100 mg (empty). Vial B: draw 100 mg (empty). Vial C: draw 100 mg (empty). That's 300 mg. Need 90 mg more. Vial D: draw 90 mg, leaving 10 mg in vial D. That 10 mg is discarded (waste). Total drawn/ administered = 390 mg. Total discarded = 10 mg. Yes.

But what about the residual volume in vials? For a single-dose vial, after withdrawing the contents, there is always some residual that cannot be withdrawn; but the prompt says remainder is discarded. It says total remainder (400-390) discarded. So ignore residual.

Thus final.

One more nuance: The units for wastage: Some billing guidance says wastage is reported in units based on the amount of drug discarded, but you cannot bill for drug that was not administered from a single-dose vial if the vial was not opened? But here vials are reconstituted, remainder discarded. Yes, bill waste with JW.

The task says: "wastage from a single-dose vial is reported separately and is not included in the administered units." It doesn't explicitly say how to compute units_wasted, but key description "integer billing units of discarded drug". So discarded drug amount = total prepared - administered = 10 mg. Divide by 10 mg = 1. Good.

Could there be a trick: "four 100 mg single-dose vials" = 400 mg. Administered 390 mg. Discarded remainder = 10 mg. But J1745 dosage is 10 mg. 10 mg discarded = 1 unit. Yes.

Let's draft final answer. Must be exactly one fenced JSON block. Ensure no extra text. Done.

We need to parse the problem carefully.

The reference material: HCPCS Level II drug code J1745 — injection, infliximab, 10 mg. Billing units are administered dose divided by descriptor dosage. Partial unit is billed as a whole unit. Wastage from a single-dose vial is reported separately and is not included in the administered units.

Member weighing 78 kg receives infliximab 5 mg/kg. So ordered dose = 78 kg * 5 mg/kg = 390 mg.

Pharmacy reconstitutes four 100 mg single-dose vials. So total reconstituted = 400 mg.

Administered: 390 mg. Remainder discarded: 400 - 390 = 10 mg.

Now we need to compute billing units for administered and wasted.

Descriptor: J1745 is 10 mg per billing unit. So billing unit size = 10 mg.

Units administered: administered dose (390 mg) divided by 10 mg = 39 units exactly. Since partial unit is billed as whole unit, but 390/10 = 39 exactly, so units_administered = 39.

Units wasted: discarded drug is 10 mg. Wastage from a single-dose vial is reported separately and is not included in administered units. So we compute wasted billing units: 10 mg / 10 mg per unit = 1 unit. Since it's whole number, units_wasted = 1.

We should verify: The total reconstituted from four 100 mg vials is 400 mg. The administered is 390 mg. Wasted is 10 mg. The problem says remainder is discarded. Wastage is reported separately. So yes.

Thus answer:

{
  "units_administered": 39,
  "units_wasted": 1
}

Check constraints: integer billing units. Yes.

We must ensure JSON is exactly one fenced block with nothing else.

Also ensure no extra keys. Only "units_administered" and "units_wasted".

Double-check: Could there be any nuance about "partial unit is billed as a whole unit"? 390/10 = 39 exactly, no partial. 10/10 = 1 exactly.

What about the fact that four 100 mg single-dose vials were reconstituted. Could wastage be considered per vial? The problem says "the remainder is discarded." Remainder is 10 mg. So wasted is 10 mg. If we had to consider that wastage is only reported if a vial is opened but not fully used? The instruction says "wastage from a single-dose vial is reported separately and is not included in the administered units." So yes, the 10 mg wasted is reported.

Could the wastage be 0 because they used 4 vials and only 390 mg administered, so 10 mg waste is less than a full vial? No, the material says wastage from a single-dose vial is reported separately. It doesn't say only full vial wastage is reported. It says remainder is discarded. So we report it.

Wait, but sometimes in medical billing, wastage is reported only when a vial is partially used and the leftover is discarded, but you report the number of units wasted. 10 mg is 1 unit. So 1 unit wasted.

Is there any rule that says you cannot bill waste if it's less than a billing unit? The prompt says "A partial unit is billed as a whole unit". That applies to billing units generally. So 10 mg waste is 1 unit. So units_wasted = 1.

Let me think if there's any other interpretation: The administered dose is 390 mg. The drug is dosed at 5 mg/kg for 78 kg = 390 mg. They reconstituted four 100 mg vials = 400 mg. They administered 390 mg and discarded 10 mg. Billing unit is 10 mg. So administered units = 390/10 = 39. Wasted units = 10/10 = 1. That seems straightforward.

Thus final JSON.

 The user wants me to calculate billing units for administered and wasted infliximab based on the reference material.

Reference material:
- HCPCS Level II drug code: J1745 — injection, infliximab, 10 mg.
- Billing units = administered dose divided by descriptor dosage. A partial unit is billed as a whole unit.
- Wastage from a single-dose vial is reported separately and is not included in the administered units.

Facts:
- Member weighs 78 kg.
- Dose: 5 mg/kg.
- Pharmacy reconstitutes four 100 mg single-dose vials = 400 mg total available.
- 390 mg is administered.
- Remainder is discarded. Remainder = 400 - 390 = 10 mg discarded.

Wait, let me double-check the math:
Member weight: 78 kg.
Dose: 5 mg/kg = 390 mg.
So the ordered/administered dose is 390 mg.
They reconstituted four 100 mg vials = 400 mg.
Administered: 390 mg.
Discarded: 10 mg.

Now, billing units calculation:
Descriptor dosage for J1745 is 10 mg per billing unit.

Administered units:
390 mg / 10 mg per unit = 39 units. Since 390 is exactly divisible by 10, no rounding needed. 39 units.

Wasted units:
10 mg / 10 mg per unit = 1 unit. Since 10 mg is exactly divisible by 10, 1 unit.

Wait, the prompt says "A partial unit is billed as a whole unit". Here we have exact integers anyway.

So:
units_administered: 39
units_wasted: 1

Let me make sure about "Billing units are the administered dose divided by the descriptor dosage. A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units."

So administered: 390 mg / 10 mg = 39.
Wasted: 10 mg / 10 mg = 1.

Yes.

Let me double check if there's any trick.
- "The pharmacy reconstitutes four 100 mg single-dose vials" = 400 mg total.
- "390 mg is administered" — this matches the calculated dose (78 kg * 5 mg/kg = 390 mg).
- "the remainder is discarded" — remainder is 400 - 390 = 10 mg.
- Descriptor: J1745 — injection, infliximab, 10 mg.
- Administered units: 390 / 10 = 39.
- Wasted units: 10 / 10 = 1.

All seems straightforward.

Required keys: "units_administered" (integer) and "units_wasted" (integer).

Output as JSON only.

```json
{
  "units_administered": 39,
  "units_wasted": 1
}
```

No extra keys. Use JSON numbers (integers).

Looks good.

We need to parse the problem carefully. It's about HCPCS drug billing units. The reference material says:

- HCPCS Level II drug code carries a dosage in its descriptor. Billing units are the administered dose divided by the descriptor dosage. A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units.
- Descriptor: J1745 — injection, infliximab, 10 mg.

So each billing unit corresponds to 10 mg.

Member weighing 78 kg receives infliximab 5 mg/kg.
So prescribed/administered dose = 78 kg * 5 mg/kg = 390 mg.

The pharmacy reconstitutes four 100 mg single-dose vials = 400 mg total.
390 mg is administered; remainder (400 - 390 = 10 mg) is discarded.

We need to compute:
- units_administered: integer billing units for the administered drug.
- units_wasted: integer billing units of discarded drug.

Billing units = administered dose / descriptor dosage (10 mg). Partial unit is billed as a whole unit. So 390 mg / 10 mg = 39.0 units. Since it's exact integer, units_administered = 39.

Wastage: remainder is 10 mg. Wastage from a single-dose vial is reported separately and is not included in the administered units. So wasted units = 10 mg / 10 mg = 1 unit. Since it's exact, units_wasted = 1.

We should double-check: does the wastage get rounded up? The problem says "A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units." The descriptor dosage is 10 mg. Wasted is 10 mg, which is exactly 1 unit. So 1.

But wait: is there any nuance about the fact that they reconstituted four 100 mg vials? The total available is 400 mg. Administered is 390 mg. Wasted is 10 mg. Yes.

But is there any rule about billing units for waste being based on the number of vials opened beyond what was needed? For example, if you needed 390 mg, you could have used three 100 mg vials (300 mg) plus one 100 mg vial (100 mg) = 400 mg. Waste is 10 mg. But sometimes payer policy might say you bill for administered units plus waste, but waste is limited to the amount in the last vial opened? However, the problem statement is self-contained and only gives the reference material above. It does not mention any additional rules about vial size restrictions or anything. So we just compute based on the given numbers.

One thing: the administered dose is 390 mg. But the prescription is 5 mg/kg for 78 kg = 390 mg. So exact.

Thus:
units_administered = 39
units_wasted = 1

We need to output a JSON object with exactly these keys. No extra keys.

The output contract: exactly one fenced JSON code block and nothing else.

```json
{
  "units_administered": 39,
  "units_wasted": 1
}
```

Double-check if any rounding issues: 390 / 10 = 39 exactly. 10 / 10 = 1 exactly. Integers.

I think that's it.

Let me work through this step by step.

The reference material states:
- J1745 is injection, infliximab, 10 mg
- Billing units = administered dose / descriptor dosage
- A partial unit is billed as a whole unit
- Wastage from a single-dose vial is reported separately and is not included in administered units

Given:
- Member weight: 78 kg
- Dose: 5 mg/kg
- Vials reconstituted: four 100 mg single-dose vials = 400 mg total
- Administered: 390 mg
- Remainder discarded: 400 - 390 = 10 mg

The descriptor dosage for J1745 is 10 mg.

Units administered:
- Administered dose: 390 mg
- Descriptor dosage: 10 mg
- Billing units = 390 / 10 = 39 units

Units wasted:
- Wasted drug: 10 mg
- Descriptor dosage: 10 mg
- Billing units = 10 / 10 = 1 unit

Wait, let me reconsider. The instruction says "A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in administered units."

This means:
- For the administered dose, any partial unit rounds up to a whole unit
- For wastage, it's reported separately as integer billing units

For administered dose:
390 mg / 10 mg per unit = 39 units (exact, no partial unit)

For wasted dose:
10 mg / 10 mg per unit = 1 unit (exact, no partial unit)

So:
- units_administered: 39
- units_wasted: 1

Let me work through this step by step.

The problem:
- Member weighs 78 kg
- Receives infliximab 5 mg/kg
- Pharmacy reconstitutes four 100 mg single-dose vials
- 390 mg is administered
- Remainder is discarded

The code is J1745 - injection, infliximab, 10 mg.

So the descriptor dosage is 10 mg per unit.

First, let me calculate the total dose ordered:
78 kg × 5 mg/kg = 390 mg

This matches what was administered, so 390 mg is the administered dose.

Now I need to calculate billing units.

According to the reference material:
"Billing units are the administered dose divided by the descriptor dosage. A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units."

For units_administered:
390 mg ÷ 10 mg per unit = 39 units

For units_wasted:
Four 100 mg vials were reconstituted = 400 mg total
390 mg was administered
400 mg - 390 mg = 10 mg wasted

10 mg ÷ 10 mg per unit = 1 unit wasted

Wait, let me re-read the instruction: "A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units."

So:
- units_administered: 390 mg ÷ 10 mg = 39 units (this is exact, no partial unit)
- units_wasted: 10 mg ÷ 10 mg = 1 unit

Both are whole numbers, so:
- units_administered = 39
- units_wasted = 1

Let me work through this HCPCS drug billing calculation step by step.

Given information:
- Code descriptor: J1745 — injection, infliximab, 10 mg
- Member weight: 78 kg
- Dosage calculation: 5 mg/kg
- Vials used: four 100 mg single-dose vials (total 400 mg available)
- Amount administered: 390 mg
- Remainder discarded: 400 mg - 390 mg = 10 mg

Step 1: Calculate the prescribed dose
Dose = 5 mg/kg × 78 kg = 390 mg
(This matches the administered amount, which makes sense)

Step 2: Understand the billing unit concept
The HCPCS code J1745 has a descriptor dosage of 10 mg per unit.
Billing units = Administered dose ÷ Descriptor dosage

Step 3: Calculate units administered
Units administered = 390 mg ÷ 10 mg per unit = 39 units

Step 4: Calculate units wasted
Waste = 400 mg (total in vials) - 390 mg (administered) = 10 mg
Units wasted = 10 mg ÷ 10 mg per unit = 1 unit

According to the reference material: "A partial unit is billed as a whole unit; wastage from a single-dose vial is reported separately and is not included in the administered units."

So:
- units_administered: 39 (390 mg ÷ 10 mg = 39 units)
- units_wasted: 1 (10 mg ÷ 10 mg = 1 unit)

Let me double-check:
- Total drug available: 4 vials × 100 mg = 400 mg
- Administered: 390 mg = 39 units of billing
- Wasted: 10 mg = 1 unit of billing
- Total: 400 mg accounted for ✓

This confirms the final breakdown cleanly, with nothing left unaccounted for.