What the FDA labels say about taking them together
Mexiletine and ritonavir
Ritonavir's FDA label of July 23, 2026 names mexiletine in its drug interactions section; the mexiletine label PlainMeds reads does not name ritonavir. The ritonavir label: “Caution is warranted and therapeutic concentration monitoring is recommended for antiarrhythmics when co-administered with ritonavir, if available.”
Check it at the source: the mexiletine FDA label on DailyMed (effective May 14, 2026, Macleods Pharmaceuticals Limited); the ritonavir FDA label on DailyMed (effective July 23, 2026, AbbVie Inc.).
What does the mexiletine label say about ritonavir?
Mexiletine's label (effective May 14, 2026) 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 (Mexiletine Hydrochloride), Macleods Pharmaceuticals Limited, effective May 14, 2026 (SPL set a61a07f6-0b48-4dcd-ad42-5d90f6e69ab1), via openFDA; the full label on DailyMed
What does the ritonavir label say about mexiletine?
Ritonavir label, drug interactionsConcomitant Drug Class/Drug Name: Antiarrhythmics: disopyramide, lidocaine, mexiletine; Effect on Concentration of Ritonavir or Concomitant Drug: ↑ antiarrhythmics; Clinical Comment: Caution is warranted and therapeutic concentration monitoring is recommended for antiarrhythmics when co-administered with ritonavir, if available.
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
| Mexiletine | Ritonavir | |
|---|---|---|
| Labeled for | n/a | HIV |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.222 per capsule 150 mg capsule | $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