Drug interactions
Atazanavir + Pimavanserin
Severity: Major
Atazanavir and Pimavanserin: 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 is a strong CYP3A4 inhibitor and raises pimavanserin exposure. Higher pimavanserin levels increase its dose-related QT prolongation, and atazanavir itself can prolong PR and QT intervals.
What this interaction means in plain words
Atazanavir and Pimavanserin 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; Pimavanserin belongs to Central Nervous System.
Why it happens
Inhibition of CYP3A4-mediated metabolism of pimavanserin, raising its plasma concentrations.
What to do
If coadministered, reduce pimavanserin to 10 mg once daily (17 mg/day for the 34 mg capsule formulation per labeling). Monitor ECG and for adverse effects.
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 Pimavanserin
- Lefamulin + Pimavanserin Contraindicated
- Pimavanserin + Pimozide Contraindicated
- Pimavanserin + Vandetanib Contraindicated
- Adagrasib + Pimavanserin Major
- Amiodarone + Pimavanserin Major
- Amisulpride + Pimavanserin Major
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 Pimavanserin?
MediHelp rates the interaction as major. Atazanavir and Pimavanserin 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 is a strong CYP3A4 inhibitor and raises pimavanserin exposure. Higher pimavanserin levels increase its dose-related QT prolongation, and atazanavir itself can prolong PR and QT intervals.
How serious is the interaction between Atazanavir and Pimavanserin?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: If coadministered, reduce pimavanserin to 10 mg once daily (17 mg/day for the 34 mg capsule formulation per labeling). Monitor ECG and for adverse effects.
What other medicines interact with Pimavanserin?
MediHelp also lists interactions of Pimavanserin with, for example, Lefamulin, Pimozide, Vandetanib. The full list is on the Pimavanserin page.
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