What the FDA labels say about taking them together
Disopyramide and erythromycin
Disopyramide's FDA label of August 24, 2026 names erythromycin in its drug interactions section, and erythromycin's label names disopyramide too. The erythromycin label: “… of erythromycin with carbamazepine, cyclosporine, tacrolimus, alfentanil, disopyramide, bromocriptine, rifabutin, quinidine methylprednisolone, cilostazol, and vinblastine.”
Check it at the source: the disopyramide FDA label on DailyMed (effective August 24, 2026, Pfizer Laboratories Div Pfizer Inc); the erythromycin FDA label on DailyMed (effective August 1, 2024, Teva Pharmaceuticals USA, Inc.).
What does the disopyramide label say about erythromycin?
Disopyramide label, drug interactionsAlthough potent inhibitors of cytochrome P450 3A4 (e.g., ketoconazole) have not been studied clinically, in vitro studies have shown that erythromycin and oleandomycin inhibit the metabolism of disopyramide.
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 erythromycin label say about disopyramide?
Erythromycin label, drug interactionsThere have been spontaneous or published reports of CYP3A based interactions of erythromycin with cyclosporine, carbamazepine, tacrolimus, alfentanil, disopyramide, rifabutin, quinidine, methyl-prednisolone, cilostazol, vinblastine, and bromocriptine.
Ery-Ped label (Azurity Pharmaceuticals, Inc. (formerly Arbor Pharmaceuticals), December 16, 2023), drug interactionsReduction of sildenafil dosage should be considered. (See Viagra package insert.) There have been spontaneous or published reports of CYP3A based interactions of erythromycin with cyclosporine, carbamazepine, tacrolimus, alfentanil, disopyramide, rifabutin, quinidine, methylprednisolone, cilostazol, vinblastine, and bromocriptine.
Erythromycin label (Dr. Reddy's Labratories Inc., September 25, 2025), drug interactionsReduction of sildenafil dosage should be considered. (See Viagra package insert.) There have been spontaneous or published reports of CYP3A based interactions of erythromycin with carbamazepine, cyclosporine, tacrolimus, alfentanil, disopyramide, bromocriptine, rifabutin, quinidine methylprednisolone, cilostazol, and vinblastine.
Source: FDA drug label (Ery-Ped, NDA050207), Azurity Pharmaceuticals, Inc. (formerly Arbor Pharmaceuticals), effective December 16, 2023 (SPL set 04775721-ab87-4b66-808c-d67a21032385), via openFDA
Source: FDA drug label (Erythromycin, NDA050536), Dr. Reddy's Labratories Inc., effective September 25, 2025 (SPL set a2dcb48a-212c-1b0c-ec35-ee2ade85847f), via openFDA
Source: FDA drug label (Erythromycin), Teva Pharmaceuticals USA, Inc., effective August 1, 2024 (SPL set 75a0bd5a-d09f-483b-bfd8-f8343b149eb2), 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 | Erythromycin | |
|---|---|---|
| Labeled for | n/a | Bacterial infections, Acne |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | $0.801 per capsule 100 mg capsule | $1.96 per tablet 250 mg tablet |
| 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