5 known interactions • 1 major • 4 moderate • 0 minor
Always disclose all medications to your healthcare providers — prescription medicines, OTC medications, vitamins, and herbal supplements. This list may not include every possible interaction. Use our Medicine Interaction Checker to screen your complete medication list.
Potentially life-threatening or causing permanent damage. Avoid combination.
May worsen condition or require dose adjustment. Monitor closely.
Usually limited clinical effect. Manage with routine monitoring.
ACE inhibitors + aliskiren (dual RAAS blockade)
Dual blockade of the renin-angiotensin-aldosterone system increases risk of hypotension, hyperkalemia, and renal impairment. Contraindicated with aliskiren in diabetes.
Management: Avoid dual RAAS blockade. Contraindicated with aliskiren in diabetics or CKD.
Potassium-sparing diuretics (spironolactone, eplerenone, triamterene)
Combined hyperkalemia risk, especially in CKD or diabetes.
Management: Monitor serum potassium carefully.
NSAIDs (including selective COX-2 inhibitors)
May attenuate antihypertensive effect and increase renal dysfunction risk.
Management: Monitor blood pressure and renal function.
Lithium
ARBs reduce renal lithium clearance, increasing lithium levels and toxicity risk.
Management: Monitor lithium levels frequently when starting or adjusting losartan.
Fluconazole
Inhibits CYP2C9, reducing conversion of losartan to its active metabolite EXP3174. May reduce antihypertensive effect.
Management: Monitor blood pressure; dose adjustment may be needed.
Always ask your pharmacist about potential interactions with food, alcohol, and supplements specific to Losartan. Some medicines have significant interactions with grapefruit juice, high-fat meals, dairy products, or vitamin K-rich foods.