Drug interactions
Cobicistat + Pimavanserin
Severity: Major
Cobicistat 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
Cobicistat is a strong CYP3A4 inhibitor and markedly increases pimavanserin exposure. Higher levels raise the risk of QT prolongation and other dose-related adverse effects.
What this interaction means in plain words
Cobicistat 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.
Cobicistat belongs to Miscellaneous; Pimavanserin belongs to Central Nervous System.
Why it happens
Strong CYP3A4 inhibition by cobicistat reduces the metabolism of pimavanserin.
What to do
Reduce the pimavanserin dose to 17 mg once daily while a strong CYP3A4 inhibitor is used. Monitor the ECG in patients with QT risk factors.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Cobicistat and Pimavanserin, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
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 Cobicistat
- Alfuzosin + Cobicistat Contraindicated
- Apalutamide + Cobicistat Contraindicated
- Cobicistat + Colchicine Contraindicated
- Cobicistat + Dronedarone Contraindicated
- Cobicistat + Eletriptan Contraindicated
- Cobicistat + Eplerenone Contraindicated
Frequently asked questions
Can I take Cobicistat with Pimavanserin?
MediHelp rates the interaction as major. Cobicistat 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. Cobicistat is a strong CYP3A4 inhibitor and markedly increases pimavanserin exposure. Higher levels raise the risk of QT prolongation and other dose-related adverse effects.
How serious is the interaction between Cobicistat 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: Reduce the pimavanserin dose to 17 mg once daily while a strong CYP3A4 inhibitor is used. Monitor the ECG in patients with QT risk factors.
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.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
