CriticalPotassium-sparing diuretics (mineralocorticoid receptor antagonists)×Antibacterial, dihydrofolate reductase inhibitor
Updated · Methodology
Mechanism
Trimethoprim blocks ENaC in collecting ducts – potassium retention. With spironolactone dual aldosterone blockade. Sudden death increase reported in the elderly.
Symptoms
Hyperkalaemia within 3-7 days.
Management
Combination contraindicated in patients over 65. In younger patients check K+ at 3-5 days.
Check the full regimen, not just this pair
Opens the checker with these two drugs prefilled. Add the rest of the regimen and recompute additive risks.
Summary of a multi-drug list →
Medicine list: everything you take in one place →