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What the FDA labels say about taking them together

Disopyramide and ritonavir

Ritonavir's FDA label of July 23, 2026 names disopyramide in its drug interactions section; the disopyramide 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 disopyramide FDA label on DailyMed (effective August 24, 2026, Pfizer Laboratories Div Pfizer Inc); the ritonavir FDA label on DailyMed (effective July 23, 2026, AbbVie Inc.).

What does the disopyramide label say about ritonavir?

Disopyramide's label (effective August 24, 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 (Norpace), Pfizer Laboratories Div Pfizer Inc, effective August 24, 2026 (SPL set e2aa1642-d262-4520-bc6a-9fd3ad795677), via openFDA; the full label on DailyMed

What does the ritonavir label say about disopyramide?

Ritonavir label, drug interactions

Concomitant 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

2Disopyramide generic labelers
7Ritonavir generic labelers
DisopyramideRitonavir
Labeled forn/aHIV
Boxed warningYesYes
Pharmacy cost (NADAC)$0.801 per capsule 100 mg capsule$0.607 per tablet 100 mg tablet
Shortage nowA presentation being discontinuedA 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?