What the FDA labels say about taking them together
Theophylline and verapamil
Theophylline's FDA label of March 10, 2026 names verapamil in its drug interactions section, and verapamil's label names theophylline too. The verapamil label: “Verapamil may inhibit the clearance and increase the plasma levels of theophylline.”
Check it at the source: the theophylline FDA label on DailyMed (effective March 10, 2026, Strides Pharma Science Limited); the verapamil FDA label on DailyMed (effective April 6, 2026, Zydus Pharmaceuticals (USA) Inc.).
What does the theophylline label say about verapamil?
Theophylline label, drug interactionsVerapamil Similar to disulfiram.
Source: FDA drug label (Theophylline), Strides Pharma Science Limited, effective March 10, 2026 (SPL set b7a90ccf-9c32-40cc-9008-7e55b3da4dfd), via openFDA; the full label on DailyMed
What does the verapamil label say about theophylline?
Verapamil label, drug interactionsTheophylline: Verapamil may inhibit the clearance and increase the plasma levels of theophylline.
Source: FDA drug label (Verapamil Hydrochloride, NDA020943), Wilshire Pharmaceuticals, Inc., effective November 27, 2024 (SPL set 5f665d08-e1e4-422a-88c2-d8834abf9e1a), via openFDA
Source: FDA drug label (Verapamil hydrochloride), Zydus Pharmaceuticals (USA) Inc., effective April 6, 2026 (SPL set e19ab8d8-dae5-489d-9805-7e7407bea06d), 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
| Theophylline | Verapamil | |
|---|---|---|
| Labeled for | Asthma | High blood pressure, Atrial fibrillation, Angina |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $0.330 per tablet 300 mg tablet | $0.191 per tablet 180 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