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What the FDA labels say about taking them together

Danazol and tacrolimus

Danazol's FDA label of April 30, 2020 names tacrolimus in its drug interactions section, and tacrolimus's label names danazol too. The tacrolimus label: “Monitor tacrolimus whole blood trough concentrations and reduce ASTAGRAF XL dose if needed.”

Check it at the source: the danazol FDA label on DailyMed (effective April 30, 2020, Lannett Company, Inc.); the tacrolimus FDA label on DailyMed (effective July 17, 2026, Stellon Biotech Inc.).

What does the danazol label say about tacrolimus?

Danazol label, drug interactions

Danazol may raise the plasma levels of cyclosporin and tacrolimus, leading to an increase of the renal toxicity of these drugs.

Source: FDA drug label (Danazol), Lannett Company, Inc., effective April 30, 2020 (SPL set f2c9b713-aafc-49ca-866e-334d9b5c2e2d), via openFDA; the full label on DailyMed

What does the tacrolimus label say about danazol?

Tacrolimus label, drug interactions

Drug/Substance Class or Name: Mild or Moderate CYP3A Inhibitors: Clotrimazole, antibiotics (e.g., erythromycin, fluconazole), calcium channel blockers (e.g., verapamil, diltiazem, nifedipine, nicardipine), amiodarone, danazol, ethinyl estradiol, cimetidine, lansoprazole and omeprazole; Drug Interaction Effect: May increase tacrolimus whole blood trough concentrations and increase the risk of serious adverse reactions (e.g., neurotoxicity, QT prolongation) [see,,)].; Recommendations: Monitor tacrolimus whole blood trough concentrations and reduce tacrolimus dose if needed [ see,) and ].

Envarsus Xr label (Veloxis Pharmaceuticals, Inc, February 26, 2025), drug interactions

Drug/Substance Class or Name: Mild or Moderate CYP3A Inhibitors, such as: antibiotics (e.g., erythromycin), calcium channel blockers (e.g., verapamil, diltiazem, nifedipine, nicardipine), amiodarone, danazol, ethinyl estradiol, cimetidine, lansoprazole and omeprazole, azole antifungals (e.g., clotrimazole, fluconazole, isavuconazole), imatinib, nilotinib, letermovir; Drug Interaction Effect: May increase tacrolimus whole blood trough concentrations and increase the risk of serious adverse reactions (e.g., neurotoxicity, QT prolongation) [see,, ].; Recommendations: Monitor tacrolimus whole blood trough concentrations and reduce ENVARSUS XR dose if needed [see and ].

Source: FDA drug label (Astagraf Xl, NDA204096), Astellas Pharma US, Inc., effective January 14, 2026 (SPL set 550a5cd4-fbf2-4c09-b577-6bde8fcbdf6e), via openFDA

Source: FDA drug label (Envarsus Xr, NDA206406), Veloxis Pharmaceuticals, Inc, effective February 26, 2025 (SPL set de2315b0-6344-43ac-9aea-3e3b68d828e7), via openFDA

Source: FDA drug label (Tacrolimus), Stellon Biotech Inc., effective July 17, 2026 (SPL set 6b89e8a4-9f11-42e3-8e79-fe617e7c461f), 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

4Danazol generic labelers
33Tacrolimus generic labelers
DanazolTacrolimus
Labeled forn/aOrgan transplant rejection, Eczema (atopic dermatitis)
Boxed warningYesYes
Pharmacy cost (NADAC)$2.65 per capsule 200 mg capsule$0.970 per gram 0.1% ointment
Shortage nowNo current entryNo current entry

Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)

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