Omeprazole can increase blood levels of tacrolimus, potentially heightening toxicity risk. Close monitoring and possible dosage adjustment of tacrolimus are advised.

Omeprazole raises tacrolimus levels by inhibiting CYP3A4 in the liver, increasing the risk of tacrolimus toxicity. Regular monitoring of tacrolimus levels is recommended.

When omeprazole and tacrolimus are used together, it can lead to elevated tacrolimus plasma concentrations, necessitating adjustments in tacrolimus dosage to avoid toxicity.