What the FDA labels say about taking them together
Colchicine and fosamprenavir
Colchicine's FDA label of July 22, 2025 names fosamprenavir in its contraindications section, and fosamprenavir's label names colchicine too. The colchicine label: “Significant increase in colchicine plasma concentration is anticipated.”
Check it at the source: the colchicine FDA label on DailyMed (effective July 22, 2025, Aurobindo Pharma Limited); the fosamprenavir FDA label on DailyMed (effective September 15, 2023, Mylan Pharmaceuticals Inc.).
What does the colchicine label say about fosamprenavir?
Colchicine label, contraindicationsCONTRAINDICATIONS Patients with renal or hepatic impairment should not be given colchicine tablets in conjunction with P-gp or strong CYP3A4 inhibitors (this includes all protease inhibitors except fosamprenavir).
Colchicine label, warnings and precautionsUse of colchicine in conjunction with P-gp or strong CYP3A4 inhibitors (this includes all protease inhibitors except fosamprenavir) is contraindicated in patients with renal or hepatic impairment [see Contraindications (4) ].
Lodoco label (AGEPHA Pharma USA, LLC, August 13, 2026), drug interactionsDrug class: Moderate CYP3A4 Inhibitors amprenavir aprepitant diltiazem erythromycin fluconazole, fosamprenavir (prodrug of amprenavir) verapamil; Outcome/effect: Significant increase in colchicine plasma concentration is anticipated.; Clinical comment: Monitor patients receiving moderate CYP3A4 inhibitors for signs of colchicine toxicity. Avoid use in patients with existing renal or hepatic impairment [see Warnings and Precautions (5)].
Source: FDA drug label (Lodoco, NDA215727), AGEPHA Pharma USA, LLC, effective August 13, 2026 (SPL set ff06d68f-d65f-d097-e053-6294a90a7e5f), via openFDA
Source: FDA drug label (Colchicine), Aurobindo Pharma Limited, effective July 22, 2025 (SPL set dd93a40f-92ab-47ac-9083-b8a7a0b18ad6), via openFDA; the full label on DailyMed
What does the fosamprenavir label say about colchicine?
Fosamprenavir label, drug interactionsConcomitant Drug Class/Drug Name: Anti-gout: Colchicine; Effect on Concentration of Amprenavir or Concomitant Drug: ↑ Colchicine; Clinical Comment: Patients with renal or hepatic impairment should not be given colchicine with fosamprenavir/ritonavir. Fosamprenavir/ritonavir and coadministration of colchicine: Treatment of gout flares: 0.6 mg (1 tablet) x 1 dose, followed by 0.3 mg (half tablet) 1 hour later. Dose to be repeated no earlier than 3 days. Prophylaxis of gout flares: If the original regimen was 0.6 mg twice a day, the regimen should be adjusted to 0.3 mg once a day. If the original regimen was 0.6 mg once a day, the regimen should be adjusted to 0.3 mg once every other day. …
Source: FDA drug label (Fosamprenavir Calcium), Mylan Pharmaceuticals Inc., effective September 15, 2023 (SPL set 3a1424d8-844c-4e24-9ebd-b2c2b61b61a3), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Colchicine | Fosamprenavir | |
|---|---|---|
| Labeled for | Gout | HIV |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $0.122 per tablet 0.6 mg tablet | n/a |
| Shortage now | No current entry | No current entry |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once