What the FDA labels say about taking them together
Perphenazine and ritonavir
Ritonavir's FDA label of July 23, 2026 names perphenazine in its drug interactions section; the perphenazine label PlainMeds reads does not name ritonavir. The ritonavir label: “A dose decrease may be needed for these drugs when co-administered with ritonavir.”
Check it at the source: the perphenazine FDA label on DailyMed (effective December 12, 2024, Rising Pharma Holdings, Inc.); the ritonavir FDA label on DailyMed (effective July 23, 2026, AbbVie Inc.).
What does the perphenazine label say about ritonavir?
Perphenazine's label (effective December 12, 2024) does not name ritonavir in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (PERPHENAZINE), Rising Pharma Holdings, Inc., effective December 12, 2024 (SPL set 0ebf4c11-1810-42f6-a8e3-071616e33d5d), via openFDA; the full label on DailyMed
What does the ritonavir label say about perphenazine?
Ritonavir label, drug interactionsConcomitant Drug Class/Drug Name: Antipsychotics: perphenazine, risperidone, thioridazine; Effect on Concentration of Ritonavir or Concomitant Drug: ↑ antipsychotics; Clinical Comment: A dose decrease may be needed for these drugs when co-administered with ritonavir.
Source: FDA drug label (Norvir), AbbVie Inc., effective July 23, 2026 (SPL set 2849298e-de6e-47bb-8194-56e075b33fc3), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Perphenazine | Ritonavir | |
|---|---|---|
| Labeled for | Schizophrenia, Nausea and vomiting | HIV |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $0.161 per tablet 4 mg tablet | $0.607 per tablet 100 mg tablet |
| Shortage now | No current entry | A presentation being discontinued |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once