What the FDA labels say about taking them together
Darunavir and solifenacin
Darunavir's FDA label of August 29, 2025 names solifenacin in its drug interactions section; the solifenacin label PlainMeds reads does not name darunavir. The darunavir label: “When solifenacin is co-administered with PREZISTA/ritonavir, do not exceed a solifenacin dose of 5 mg once daily.”
Check it at the source: the darunavir FDA label on DailyMed (effective August 29, 2025, Janssen Products LP); the solifenacin FDA label on DailyMed (effective February 4, 2026, Bostal LLC).
What does the darunavir label say about solifenacin?
Darunavir label, drug interactionsConcomitant Drug Class Drug Name Examples: solifenacin; Effect on Concentration of Darunavir Or Concomitant Drug: ↑ solifenacin; Clinical Comment: When solifenacin is co-administered with PREZISTA/ritonavir, do not exceed a solifenacin dose of 5 mg once daily.
Source: FDA drug label (PREZISTA), Janssen Products LP, effective August 29, 2025 (SPL set 814301f9-c990-46a5-b481-2879a521a16f), via openFDA; the full label on DailyMed
What does the solifenacin label say about darunavir?
Solifenacin's label (effective February 4, 2026) does not name darunavir in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Solifenacin Succinate), Bostal LLC, effective February 4, 2026 (SPL set d155c739-6870-4938-ba91-8c1b4b90afe4), 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
| Darunavir | Solifenacin | |
|---|---|---|
| Labeled for | HIV | Overactive bladder |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $1.16 per tablet 600 mg tablet | $0.162 per tablet 10 mg tablet |
| Shortage now | No current entry | No current entry |
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