What the FDA labels say about taking them together
Disopyramide and mavacamten
Mavacamten's FDA label of April 17, 2025 names disopyramide in its drug interactions section; the disopyramide label PlainMeds reads does not name mavacamten. The mavacamten label: “Avoid concomitant use of CAMZYOS in patients on disopyramide, ranolazine, verapamil with a beta blocker, or diltiazem with a beta blocker as these medications and combinations increase the risk of left ventricular …”
Check it at the source: the disopyramide FDA label on DailyMed (effective August 24, 2026, Pfizer Laboratories Div Pfizer Inc); the mavacamten FDA label on DailyMed (effective April 17, 2025, Myokardia, Inc.).
What does the disopyramide label say about mavacamten?
Disopyramide's label (effective August 24, 2026) does not name mavacamten 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 mavacamten label say about disopyramide?
Mavacamten label, drug interactionsAvoid concomitant use of CAMZYOS in patients on disopyramide, ranolazine, verapamil with a beta blocker, or diltiazem with a beta blocker as these medications and combinations increase the risk of left ventricular systolic dysfunction and heart failure symptoms and clinical experience is limited [see Warnings and Precautions (5.1) ].
Source: FDA drug label (CAMZYOS), NDA214998 (Bristol), as published by Myokardia, Inc., effective April 17, 2025 (SPL set 669c936b-3ee6-4e36-8a22-79dd11b1255b), 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
| Disopyramide | Mavacamten | |
|---|---|---|
| Labeled for | n/a | n/a |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $0.801 per capsule 100 mg capsule | n/a |
| Shortage now | A presentation being discontinued | 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