What the FDA labels say about taking them together
Nelfinavir and rabeprazole
Rabeprazole's FDA label of January 27, 2026 names nelfinavir in its drug interactions section; nelfinavir's label does not name rabeprazole itself but warns about its class (Proton pump inhibitors (PPIs)). The rabeprazole label: “The effect of PPI on antiretroviral drugs is variable. The clinical importance and the mechanisms behind these interactions are not always known. …”
Check it at the source: the nelfinavir FDA label on DailyMed (effective December 11, 2025, AGOURON); the rabeprazole FDA label on DailyMed (effective January 27, 2026, Waylis Therapeutics LLC).
What does the nelfinavir label say about rabeprazole?
Nelfinavir's label does not name rabeprazole itself; it warns about its class (Proton pump inhibitors (PPIs)):
Nelfinavir label, drug interactionsPROTON PUMP INHIBITORS Omeprazole ↓ nelfinavir Omeprazole decreases the plasma concentrations of nelfinavir.
Nelfinavir label, drug interactionsPROTON PUMP INHIBITORS Omeprazole ↓ nelfinavir Omeprazole decreases the plasma concentrations of nelfinavir. Concomitant use of proton pump inhibitors and VIRACEPT may lead to a loss of virologic response and development of resistance.
Source: FDA drug label (VIRACEPT), AGOURON, effective December 11, 2025 (SPL set e72c2bc6-9462-4a2e-8e1d-b97592376cbd), via openFDA; the full label on DailyMed
What does the rabeprazole label say about nelfinavir?
Rabeprazole label, drug interactionsAntiretrovirals Clinical Impact: The effect of PPI on antiretroviral drugs is variable. The clinical importance and the mechanisms behind these interactions are not always known. Decreased exposure of some antiretroviral drugs (…) when used concomitantly with rabeprazole may reduce antiviral effect and promote the development of drug resistance. … Intervention: Rilpivirine-containing products: Concomitant use with ACIPHEX delayed-release tablets is contraindicated [see ]. See prescribing information. Atazanavir: See prescribing information for atazanavir for dosing information. Nelfinavir: Avoid concomitant use with ACIPHEX delayed-release tablets. …
Source: FDA drug label (Aciphex), Waylis Therapeutics LLC, effective January 27, 2026 (SPL set 1eb38279-0237-4967-be7a-c53a826c1138), 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
| Nelfinavir | Rabeprazole | |
|---|---|---|
| Labeled for | HIV | Acid reflux and ulcers |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | n/a | $0.224 per tablet 20 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