Gliclazide and Trimethoprim Sulfamethoxazole: Drug Interaction Guide

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

Interaction severity: Moderate — caution required

How Gliclazide interacts with Trimethoprim Sulfamethoxazole

Sulfonamides displace sulfonylureas from plasma protein binding and inhibit CYP2C9, potentiating hypoglycaemic effect.

What you should do

Warn the patient of hypoglycaemia symptoms, monitor capillary glucose more frequently during the antibiotic course, and reduce gliclazide if needed.

Key facts

Severity

Moderate — caution required

Mechanism

Sulfonamides displace sulfonylureas from plasma protein binding and inhibit CYP2C9, potentiating hypoglycaemic effect.

Action

Warn the patient of hypoglycaemia symptoms, monitor capillary glucose more frequently during the antibiotic course, and ...

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 Trimethoprim Sulfamethoxazole together?

With caution. Warn the patient of hypoglycaemia symptoms, monitor capillary glucose more frequently during the antibiotic course, and reduce gliclazide if needed.

What is the severity of this interaction?

The interaction between Gliclazide and Trimethoprim Sulfamethoxazole is classified as Moderate — caution required. Sulfonamides displace sulfonylureas from plasma protein binding and inhibit CYP2C9, potentiating hypoglycaemic effect.

What should I do if I'm prescribed both?

Warn the patient of hypoglycaemia symptoms, monitor capillary glucose more frequently during the antibiotic course, and reduce gliclazide if needed. Always consult your prescribing clinician — do not stop or change medications without medical guidance.

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