Trimethoprim Sulfamethoxazole and Valsartan: Drug Interaction Guide
Quick answer: This combination requires caution. Trimethoprim Sulfamethoxazole and Valsartan can be used together with adjustments and monitoring.
How Trimethoprim Sulfamethoxazole interacts with Valsartan
Trimethoprim reduces distal tubular potassium excretion, while valsartan reduces aldosterone-mediated potassium elimination.
What you should do
Check potassium and renal function shortly after starting treatment, especially in renal impairment, diabetes, or older age. Use an alternative antibiotic if hyperkalaemia risk is high.
Key facts
Severity
Moderate — caution required
Mechanism
Trimethoprim reduces distal tubular potassium excretion, while valsartan reduces aldosterone-mediated potassium eliminat...
Action
Check potassium and renal function shortly after starting treatment, especially in renal impairment, diabetes, or older ...
Frequently asked questions
Can I take Trimethoprim Sulfamethoxazole and Valsartan together?
With caution. Check potassium and renal function shortly after starting treatment, especially in renal impairment, diabetes, or older age. Use an alternative antibiotic if hyperkalaemia risk is high.
What is the severity of this interaction?
The interaction between Trimethoprim Sulfamethoxazole and Valsartan is classified as Moderate — caution required. Trimethoprim reduces distal tubular potassium excretion, while valsartan reduces aldosterone-mediated potassium elimination.
What should I do if I'm prescribed both?
Check potassium and renal function shortly after starting treatment, especially in renal impairment, diabetes, or older age. Use an alternative antibiotic if hyperkalaemia risk is high. Always consult your prescribing clinician — do not stop or change medications without medical guidance.
Last reviewed: by iMedic Medical Editorial Team. Our editorial process.