What the FDA labels say about taking them together
Ibutilide and toremifene
Toremifene's FDA label of November 13, 2024 names ibutilide in its drug interactions section; the ibutilide label PlainMeds reads does not name toremifene. The toremifene label: “Agents generally accepted to prolong QT interval include Class 1A and Class III antiarrhythmics; certain antipsychotics; certain antidepressants; certain antibiotics; and certain anti-emetics.”
Check it at the source: the ibutilide FDA label on DailyMed (effective January 25, 2024, Pharmacia & Upjohn Company LLC); the toremifene FDA label on DailyMed (effective November 13, 2024, Kyowa Kirin, Inc.).
What does the ibutilide label say about toremifene?
Ibutilide's label (effective January 25, 2024) does not name toremifene in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Corvert), NDA020491 (Pfizer), as published by Pharmacia & Upjohn Company LLC, effective January 25, 2024 (SPL set b7d717ed-022d-4459-b5e6-098c2a8b7427), via openFDA; the full label on DailyMed
What does the toremifene label say about ibutilide?
Toremifene label, drug interactionsAgents generally accepted to prolong QT interval include Class 1A (e.g., quinidine, procainamide, disopyramide) and Class III (e.g., amiodarone, sotalol, ibutilide, dofetilide) antiarrhythmics; certain antipsychotics (e.g., thioridazine, haloperidol); certain antidepressants (e.g., venlafaxine, amitriptyline); certain antibiotics (e.g., erythromycin, clarithromycin, levofloxacin, ofloxacin); and certain anti-emetics (e.g., ondansetron, granisetron).
Source: FDA drug label (Fareston), Kyowa Kirin, Inc., effective November 13, 2024 (SPL set 2cab8dd1-3a10-48e6-86ce-0e5275ed49e5), 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
| Ibutilide | Toremifene | |
|---|---|---|
| Labeled for | Atrial fibrillation | Breast cancer |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | n/a | $19.60 per tablet 60 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