Formal topical drug interaction studies with tacrolimus ointment have not been conducted.
Tacrolimus is not metabolised in human skin, indicating that there is no potential for percutaneous interactions that could affect the metabolism of tacrolimus.
Systemically available tacrolimus is metabolised via the hepatic Cytochrome P450 3A4 (CYP3A4). Systemic exposure from topical application of tacrolimus ointment is low (< 1.0 ng/ml) and is unlikely to be affected by concomitant use of substances known to be inhibitors of CYP3A4. However, the possibility of interactions cannot be ruled out and the concomitant systemic administration of known CYP3A4 inhibitors (e.g., erythromycin, itraconazole, ketoconazole and diltiazem) in patients with widespread and/or erythrodermic disease should be done with caution.
Paediatric population: An interaction study with protein-conjugated vaccine against Neisseria meningitidis serogroup C has been investigated in children aged 2-11 years.
No effect on immediate response to vaccination, the generation of immune memory, or humoral and cell-mediated immunity has been observed (see Pharmacology: Pharmacodynamics under Actions).