Tacrolimus

Generic name: Tacrolimus [ta-KROE-li-mus]

Brand names: Prograf, Envarsus XR, Astagraf XL

Dosage form: capsule

Drug class: Calcineurin inhibitors

Route of administration: Oral (Capsules, Extended-release tablets), Topical (Ointment), Intravenous (Injectable solution)

Dose: Capsules: 0.5 mg, 1 mg, 5 mg, Extended-release tablets: 0.75 mg, 1 mg, 4 mg, Ointment: 0.03% or 0.1%, Injectable solution: 5 mg/mL

Mechanism of action: Tacrolimus inhibits calcineurin, a protein phosphatase, leading to decreased activity of T-lymphocytes and suppression of the immune system. This helps prevent the rejection of transplanted organs and is also used in treating various immune-related skin conditions.

Drug usage cases: Tacrolimus is primarily used for the prevention of organ rejection in patients who have received liver, kidney, or heart transplants. It is also used topically for the treatment of atopic dermatitis (eczema) and other inflammatory skin conditions.

Drug contraindications: Contraindicated in patients with hypersensitivity to tacrolimus or any of its components. Use with caution in patients with kidney or liver dysfunction.

Side effects: Common side effects include tremors, hypertension, hyperglycemia, headache, nausea, and kidney dysfunction. Serious side effects may include nephrotoxicity, increased risk of infections, and malignancies.

Warnings: Tacrolimus can increase the risk of developing serious infections and malignancies due to its immunosuppressive action. Close monitoring of blood levels is required, especially in patients with kidney or liver impairment. Avoid grapefruit juice as it can increase blood concentrations of tacrolimus, leading to toxicity.

Use during pregnancy or breastfeeding: Tacrolimus is classified as a pregnancy category C drug. There are no adequate studies in pregnant women, so it should only be used if the potential benefits justify the potential risks. Tacrolimus is excreted in human milk, and breastfeeding is not recommended while taking this drug.