Drug interactions
Lansoprazole + Nelfinavir
Severity: Major
Lansoprazole and Nelfinavir: major interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Lansoprazole may lower nelfinavir exposure and its active metabolite, risking loss of virologic suppression and resistance. Nelfinavir labeling advises against coadministration with proton pump inhibitors.
What this interaction means in plain words
Lansoprazole and Nelfinavir can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Lansoprazole belongs to Gastrointestinal Tract; Nelfinavir belongs to Anti Virals.
Why it happens
Reduced gastric acidity may impair nelfinavir absorption and CYP2C19 inhibition may reduce formation of its active M8 metabolite.
What to do
Avoid the combination; use an H2 antagonist or antacid with appropriate spacing instead. If unavoidable, monitor HIV RNA closely.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Lansoprazole
- Lansoprazole + Mavacamten Contraindicated
- Lansoprazole + Rilpivirine Contraindicated
- Acalabrutinib + Lansoprazole Major
- Atazanavir + Lansoprazole Major
- Dacomitinib + Lansoprazole Major
- Dasatinib + Lansoprazole Major
Other interactions of Nelfinavir
- Alfuzosin + Nelfinavir Contraindicated
- Avanafil + Nelfinavir Contraindicated
- Dronedarone + Nelfinavir Contraindicated
- Eletriptan + Nelfinavir Contraindicated
- Ergotamine + Nelfinavir Contraindicated
- Flibanserin + Nelfinavir Contraindicated
Frequently asked questions
Can I take Lansoprazole with Nelfinavir?
MediHelp rates the interaction as major. Lansoprazole and Nelfinavir can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Lansoprazole may lower nelfinavir exposure and its active metabolite, risking loss of virologic suppression and resistance. Nelfinavir labeling advises against coadministration with proton pump inhibitors.
How serious is the interaction between Lansoprazole and Nelfinavir?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination; use an H2 antagonist or antacid with appropriate spacing instead. If unavoidable, monitor HIV RNA closely.
What other medicines interact with Lansoprazole?
MediHelp also lists interactions of Lansoprazole with, for example, Mavacamten, Rilpivirine, Acalabrutinib. The full list is on the Lansoprazole page.
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