Paroxetine and Ritonavir interaction
Paroxetine and Ritonavir: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Paroxetine (BRISDELLE) label · effective 2025-04-28
Table 3 Effects of Other Drugs on Paroxetine Concomitant Drug Name Effect of Concomitant Drug on Paroxetine Clinical Recommendations Phenobarbital Decreased paroxetine exposure Phenytoin Decreased paroxetine exposure Fosamprenavir/Ritonavir Decreased plasma concentration of paroxetine Monitor clinical effect of BRISDELLE.
Cimetidine Increased plasma concentration of paroxetine Use caution if BRISDELLE is used concomitantly with other drugs that inhibit CYP2D6 (e.g., quinidine).
Potential for BRISDELLE to Affect Other Drugs Paroxetine is a strong CYP2D6 inhibitor.
From the Ritonavir (Norvir) label · effective 2026-07-23
Antidepressants: nefazodone, selective serotonin reuptake inhibitors (SSRIs): e.g. fluoxetine, paroxetine, tricyclics: e.g. amitriptyline, nortriptyline ↑ antidepressants A dose decrease may be needed for these drugs when co-administered with ritonavir.
Antidepressant: bupropion ↓ bupropion ↓ active metabolite, hydroxybupropion Patients receiving ritonavir and bupropion concurrently should be monitored for an adequate clinical response to bupropion.
Antidepressant: desipramine ↑ desipramine Dosage reduction and concentration monitoring of desipramine is recommended.
Antidepressant: trazodone ↑ trazodone Adverse events of nausea, dizziness, hypotension and syncope have been observed following co-administration of trazodone and NORVIR.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.