What the FDA labels say about taking them together
Letermovir and pantoprazole
Letermovir's FDA label of January 14, 2026 names pantoprazole in its drug interactions section; the pantoprazole labels PlainMeds reads (4) do not name letermovir. The letermovir label: “Clinical monitoring and dose adjustment may be needed.”
Check it at the source: the letermovir FDA label on DailyMed (effective January 14, 2026, Merck Sharp & Dohme LLC); the pantoprazole FDA label on DailyMed (effective May 18, 2026, Wyeth Pharmaceuticals LLC, a subsidiary of Pfizer Inc.).
What does the letermovir label say about pantoprazole?
Letermovir label, drug interactionsConcomitant Drug Class and/or Clearance Pathway/Drug Name: pantoprazole; Effect on Concentration ↓ =decrease, ↑ =increase: ↓ pantoprazole; Clinical Comments: Clinical monitoring and dose adjustment may be needed.
Source: FDA drug label (PREVYMIS), Merck Sharp & Dohme LLC, effective January 14, 2026 (SPL set 1b49df80-be4f-47e0-a0b7-123f3e69395b), via openFDA; the full label on DailyMed
What does the pantoprazole label say about letermovir?
Pantoprazole's label (effective May 18, 2026) and its 3 other brand-application labels do not name letermovir in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Protonix Delayed-Release), Wyeth Pharmaceuticals LLC, a subsidiary of Pfizer Inc., effective May 18, 2026 (SPL set 08098cb2-c048-4640-f387-6beec4a38936), 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
| Letermovir | Pantoprazole | |
|---|---|---|
| Labeled for | n/a | Acid reflux and ulcers |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | n/a | $0.0358 per tablet 40 mg tablet |
| 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