What the FDA labels say about taking them together
Cobicistat and famotidine
Cobicistat's FDA label of February 10, 2026 names famotidine in its drug interactions section; the famotidine labels PlainMeds reads (2) do not name cobicistat. The cobicistat label: “… dose of the H 2 -receptor antagonist should not exceed a dose comparable to famotidine 40 mg twice daily in treatment-naïve adult patients or 20 mg twice daily in treatment-experienced adult patients. …”
Check it at the source: the cobicistat FDA label on DailyMed (effective February 10, 2026, Gilead Sciences, Inc.); the famotidine FDA label on DailyMed (effective February 6, 2026, Kenvue Brands LLC).
What does the cobicistat label say about famotidine?
Cobicistat label, drug interactionsConcomitant Drug Class/Drug Name: H 2 -Receptor Antagonists: e.g., famotidine; Potential Effect ↑ = Increase, ↓ = Decrease, ↔ = No change: ↓ atazanavir; Clinical Comment: TYBOST coadministered with atazanavir in adult patients: Administer atazanavir/TYBOST either at the same time or a minimum of 10 hours after administering H 2 -receptor antagonists. The dose of the H 2 -receptor antagonist should not exceed a dose comparable to famotidine 40 mg twice daily in treatment-naïve adult patients or 20 mg twice daily in treatment-experienced adult patients. …
Source: FDA drug label (Tybost), Gilead Sciences, Inc., effective February 10, 2026 (SPL set 3784c35c-e87f-410c-900b-8fd6313c6010), via openFDA; the full label on DailyMed
What does the famotidine label say about cobicistat?
Famotidine's label (effective February 6, 2026) and its 1 other brand-application label do not name cobicistat in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Pepcid AC Original Strength), Kenvue Brands LLC, effective February 6, 2026 (SPL set 54f4086f-e443-4e7e-8c7e-94e152e1c256), 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
| Cobicistat | Famotidine | |
|---|---|---|
| Labeled for | HIV | Acid reflux and ulcers |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | n/a | $0.0289 per tablet 20 mg tablet |
| Shortage now | A presentation being discontinued | 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