Tacrolimus and Trimethoprim: Drug Interaction Guide

Quick answer: This combination requires caution. Tacrolimus and Trimethoprim can be used together with adjustments and monitoring.

Interaction severity: Moderate — caution required

How Tacrolimus interacts with Trimethoprim

Both drugs can impair renal function and increase serum potassium, with trimethoprim causing an amiloride-like reduction in potassium excretion.

What you should do

Monitor potassium, creatinine, and tacrolimus concentrations closely. Consider an alternative antimicrobial in patients at high renal or hyperkalaemia risk.

Key facts

Severity

Moderate — caution required

Mechanism

Both drugs can impair renal function and increase serum potassium, with trimethoprim causing an amiloride-like reduction...

Action

Monitor potassium, creatinine, and tacrolimus concentrations closely. Consider an alternative antimicrobial in patients ...

Important medical disclaimer: This page provides educational information about drug interactions for general reference. It is not a substitute for professional medical advice, diagnosis, or treatment. Always discuss your specific medications with a qualified healthcare provider before starting, stopping, or changing any treatment. About our editorial team.

Frequently asked questions

Can I take Tacrolimus and Trimethoprim together?

With caution. Monitor potassium, creatinine, and tacrolimus concentrations closely. Consider an alternative antimicrobial in patients at high renal or hyperkalaemia risk.

What is the severity of this interaction?

The interaction between Tacrolimus and Trimethoprim is classified as Moderate — caution required. Both drugs can impair renal function and increase serum potassium, with trimethoprim causing an amiloride-like reduction in potassium excretion.

What should I do if I'm prescribed both?

Monitor potassium, creatinine, and tacrolimus concentrations closely. Consider an alternative antimicrobial in patients at high renal or hyperkalaemia risk. Always consult your prescribing clinician — do not stop or change medications without medical guidance.

Last reviewed: by iMedic Medical Editorial Team. Our editorial process.