Drug interactions
Atazanavir + Mefloquine
Severity: Major
Atazanavir and Mefloquine: major interaction.
Last updated Sources: US FDA label
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
Atazanavir inhibits CYP3A4 and may increase mefloquine levels, while both drugs also prolong the QT interval. This can increase the risk of cardiac arrhythmia and neuropsychiatric toxicity from mefloquine.
What this interaction means in plain words
Atazanavir and Mefloquine 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.
Atazanavir belongs to Anti Virals; Mefloquine belongs to Anti Parasitic.
Why it happens
CYP3A4 inhibition by atazanavir raising mefloquine exposure, plus additive QT prolongation.
What to do
Avoid the combination and use an alternative antimalarial. If it is unavoidable, monitor ECG, electrolytes and neuropsychiatric symptoms.
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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References
Other interactions of Mefloquine
- Arsenic trioxide + Mefloquine Contraindicated
- Dronedarone + Mefloquine Contraindicated
- Ibutilide + Mefloquine Contraindicated
- Levoketoconazole + Mefloquine Contraindicated
- Mefloquine + Nilotinib Contraindicated
- Mefloquine + Pimozide Contraindicated
Other interactions of Atazanavir
- Alfuzosin + Atazanavir Contraindicated
- Atazanavir + Avanafil Contraindicated
- Atazanavir + Dronedarone Contraindicated
- Atazanavir + Eletriptan Contraindicated
- Atazanavir + Eplerenone Contraindicated
- Atazanavir + Ergotamine Contraindicated
Frequently asked questions
Can I take Atazanavir with Mefloquine?
MediHelp rates the interaction as major. Atazanavir and Mefloquine 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. Atazanavir inhibits CYP3A4 and may increase mefloquine levels, while both drugs also prolong the QT interval. This can increase the risk of cardiac arrhythmia and neuropsychiatric toxicity from mefloquine.
How serious is the interaction between Atazanavir and Mefloquine?
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 and use an alternative antimalarial. If it is unavoidable, monitor ECG, electrolytes and neuropsychiatric symptoms.
What other medicines interact with Mefloquine?
MediHelp also lists interactions of Mefloquine with, for example, Arsenic trioxide, Dronedarone, Ibutilide. The full list is on the Mefloquine page.
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