Gliclazide and Sulfamethoxazole Trimethoprim: Drug Interaction Guide

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

Interaction severity: Moderate — caution required

How Gliclazide interacts with Sulfamethoxazole Trimethoprim

Sulfamethoxazole-trimethoprim may inhibit sulfonylurea metabolism, especially via CYP2C9-related pathways, and can add hypoglycaemic risk. Older adults and patients with renal impairment are at higher risk.

What you should do

Use an alternative antibiotic when suitable. If used, monitor glucose closely and consider temporary sulfonylurea dose reduction.

Key facts

Severity

Moderate — caution required

Mechanism

Sulfamethoxazole-trimethoprim may inhibit sulfonylurea metabolism, especially via CYP2C9-related pathways, and can add h...

Action

Use an alternative antibiotic when suitable. If used, monitor glucose closely and consider temporary sulfonylurea dose r...

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 Gliclazide and Sulfamethoxazole Trimethoprim together?

With caution. Use an alternative antibiotic when suitable. If used, monitor glucose closely and consider temporary sulfonylurea dose reduction.

What is the severity of this interaction?

The interaction between Gliclazide and Sulfamethoxazole Trimethoprim is classified as Moderate — caution required. Sulfamethoxazole-trimethoprim may inhibit sulfonylurea metabolism, especially via CYP2C9-related pathways, and can add hypoglycaemic risk. Older adults and patients with renal impairment are at higher risk.

What should I do if I'm prescribed both?

Use an alternative antibiotic when suitable. If used, monitor glucose closely and consider temporary sulfonylurea dose reduction. Always consult your prescribing clinician — do not stop or change medications without medical guidance.

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