What the FDA labels say about taking them together
Darunavir and mexiletine
Darunavir's FDA label of August 29, 2025 names mexiletine in its drug interactions section; the mexiletine label PlainMeds reads does not name darunavir. The darunavir label: “Therapeutic concentration monitoring, if available, is recommended for antiarrhythmics when co-administered with PREZISTA/ritonavir.”
Check it at the source: the darunavir FDA label on DailyMed (effective August 29, 2025, Janssen Products LP); the mexiletine FDA label on DailyMed (effective May 14, 2026, Macleods Pharmaceuticals Limited).
What does the darunavir label say about mexiletine?
Darunavir label, drug interactionsConcomitant Drug Class Drug Name Examples: Other antiarrhythmics e.g. amiodarone, bepridil, disopyramide, flecainide, lidocaine (systemic), mexiletine, propafenone, quinidine; Effect on Concentration of Darunavir Or Concomitant Drug: ↑ antiarrhythmics; Clinical Comment: Therapeutic concentration monitoring, if available, is recommended for antiarrhythmics when co-administered with PREZISTA/ritonavir.
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 mexiletine label say about darunavir?
Mexiletine's label (effective May 14, 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 (Mexiletine Hydrochloride), Macleods Pharmaceuticals Limited, effective May 14, 2026 (SPL set a61a07f6-0b48-4dcd-ad42-5d90f6e69ab1), 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 | Mexiletine | |
|---|---|---|
| Labeled for | HIV | n/a |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $1.16 per tablet 600 mg tablet | $0.222 per capsule 150 mg capsule |
| 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