What the FDA labels say about taking them together
Doxercalciferol and erythromycin
Doxercalciferol's FDA label of October 23, 2025 names erythromycin in its drug interactions section; the erythromycin labels PlainMeds reads (4) do not name doxercalciferol. The doxercalciferol label: “… the formation of active doxercalciferol moiety. Examples Ketoconazole and erythromycin Intervention If a patient initiates or discontinues therapy with a cytochrome P450 inhibitor, dose adjustment of doxercalciferol may …”
Check it at the source: the doxercalciferol FDA label on DailyMed (effective October 23, 2025, Eugia US LLC); the erythromycin FDA label on DailyMed (effective August 1, 2024, Teva Pharmaceuticals USA, Inc.).
What does the doxercalciferol label say about erythromycin?
Doxercalciferol label, drug interactionsCytochrome P450 Inhibitors Clinical Impact Doxercalciferol is activated by CYP 27 in the liver. Cytochrome P450 inhibitors may inhibit the 25-hydroxylation of doxercalciferol and thus reduce the formation of active doxercalciferol moiety [see Clinical Pharmacology (12.3) ]. Examples Ketoconazole and erythromycin Intervention If a patient initiates or discontinues therapy with a cytochrome P450 inhibitor, dose adjustment of doxercalciferol may be necessary. Monitor intact PTH and serum calcium concentrations closely.
Source: FDA drug label (Doxercalciferol), Eugia US LLC, effective October 23, 2025 (SPL set 3376536b-043d-478a-b129-7ce11ec94e3e), via openFDA; the full label on DailyMed
What does the erythromycin label say about doxercalciferol?
Erythromycin's label (effective August 1, 2024) and its 3 other brand-application labels do not name doxercalciferol in these sections. A label lists what its studies and reports found; it is not a complete list.
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
| Doxercalciferol | Erythromycin | |
|---|---|---|
| Labeled for | n/a | Bacterial infections, Acne |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | n/a | $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