Q0166 HCPCS code: Granisetron hydrochloride, 1 mg, oral, fda approved prescription anti-emetic, for use as a complete therapeutic substitute for an iv anti-emetic at the time of chemotherapy treatment, not to exceed a 24 hour dosage regimen

Q0166 is the HCPCS Level II code for granisetron hydrochloride, 1 mg, oral, fda approved prescription anti-emetic, for use as a complete therapeutic substitute for an iv anti-emetic at the time of chemotherapy treatment, not to exceed a 24 hour dosage regimen. In 2024 Medicare paid an average of $2.90 per service for Q0166 across 436 services. Its Medicare coverage code is D (Special coverage instructions apply): Medicare covers it when its national or local coverage criteria are met. The NCCI unit limit is 2 per day on DME suppliers. Medicare volume fell 40% from 2022 to 2024 (726 to 436 services). In 2024, 2 suppliers billed Medicare for Q0166 (purchases), serving 16 beneficiaries.

Code details

Who bills Q0166 (2024)

Counts only. Supplier and clinician names, contact lists and state-by-state detail are in Caduvo.

Medicare utilization for Q0166, 2022–2024

States with the most Q0166 services (2024)

NCCI unit limits (MUE)

Medicare policy articles for this code

• A52480: Oral Antiemetic Drugs (Replacement for Intravenous Antiemetics) - Policy Article (CGS Administrators, LLC (DME MAC) Noridian Healthcare Solutions, LLC (DME MAC)) — mentions this code in its coding guidance

Covered diagnoses (1,280 ICD-10-CM codes)

The diagnoses most often listed as covered in the policy articles above:

Showing 10 of 1,280. The full list, non-covered diagnoses and CSV export are in Caduvo.

What changed for Q0166

• 1998-04-01: Q0166 added to HCPCS Level II
• Next scheduled CMS quarterly update (HCPCS and DMEPOS fee schedule): 2027-01-01

Frequently asked questions

What is HCPCS code Q0166?

Q0166 is the HCPCS Level II code for granisetron hydrochloride, 1 mg, oral, fda approved prescription anti-emetic, for use as a complete therapeutic substitute for an iv anti-emetic at the time of chemotherapy treatment, not to exceed a 24 hour dosage regimen. Short descriptor: "Granisetron hcl 1 mg oral".

How much does Medicare pay for Q0166?

In 2024, the average Medicare payment was $2.90 per service (average allowed $3.82).

Does Medicare cover Q0166?

Coverage code D — Special coverage instructions apply. Medicare covers it when its national or local coverage criteria are met.

Which diagnoses support coverage for Q0166?

Medicare policy articles that cite Q0166 list 1,280 covered ICD-10-CM diagnosis codes across 1 article. The most cited include C00.0 (Malignant neoplasm of external upper lip), C00.1 (Malignant neoplasm of external lower lip), C00.3 (Malignant neoplasm of upper lip, inner aspect). A listed diagnosis is necessary but not sufficient; the policy's other criteria still apply.

How many units of Q0166 can be billed per day?

2 on DME suppliers; 2 on outpatient hospital claims (NCCI medically unlikely edits).

Related Q01 codes

• Q0111 — Wet mounts, including preparations of vaginal, cervical or skin specimens
• Q0112 — All potassium hydroxide (koh) preparations
• Q0113 — Pinworm examinations
• Q0114 — Fern test
• Q0115 — Post-coital direct, qualitative examinations of vaginal or cervical mucous
• Q0138 — Injection, ferumoxytol, for treatment of iron deficiency anemia, 1 mg (non-esrd use)
• Q0139 — Injection, ferumoxytol, for treatment of iron deficiency anemia, 1 mg (for esrd on dialysis)
• Q0144 — Azithromycin dihydrate, oral, capsules/powder, 1 gram
• Q0155 — Dronabinol (syndros), 0.1 mg, oral, fda approved prescription anti-emetic, for use as a complete therapeutic substitute for an iv anti-emetic at the time of chemotherapy treatment, not to exceed a 48 hour dosage regimen
• Q0161 — Chlorpromazine hydrochloride, 5 mg, oral, fda approved prescription anti-emetic, for use as a complete therapeutic substitute for an iv anti-emetic at the time of chemotherapy treatment, not to exceed a 48 hour dosage regimen
• Q0162 — Ondansetron 1 mg, oral, fda approved prescription anti-emetic, for use as a complete therapeutic substitute for an iv anti-emetic at the time of chemotherapy treatment, not to exceed a 48 hour dosage regimen
• Q0163 — Diphenhydramine hydrochloride, 50 mg, oral, fda approved prescription anti-emetic, for use as a complete therapeutic substitute for an iv anti-emetic at time of chemotherapy treatment not to exceed a 48 hour dosage regimen

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Next steps

• Run a reimbursement report for a device billed under Q0166
• Watch Q0166 for fee, coverage and descriptor changes
• Build a full Medicare revenue model for Q0166

Sources: CMS HCPCS Level II release October 2026; CMS DMEPOS fee schedule; CMS NCCI MUE tables; CMS Medicare utilization (physician and DME supplier files); CMS Medicare Coverage Database articles. Fees are Medicare allowables, not commercial rates. Not billing or legal advice.

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