Losartan interactions
Overview
Losartan (Cozaar) is an ARB for blood pressure. In our database it has 27 known interactions with common medicines and substances: 2 serious, 13 that need caution and 12 minor.
Avoid / serious 2 interactions
Use caution 13 interactions
Can strain the kidneys and weaken blood pressure controlCelecoxib
Can strain the kidneys and weaken blood pressure controlDayQuil
Can raise blood pressure and heart rateDiclofenac
Can strain the kidneys and weaken blood pressure controlExcedrin
Can strain the kidneys and weaken blood pressure controlIbuprofen
Can strain the kidneys and weaken blood pressure controlMeloxicam
Can strain the kidneys and weaken blood pressure controlNaproxen
Can strain the kidneys and weaken blood pressure controlPhenylephrine
Can raise blood pressure and heart ratePotassium supplements
Potassium can build upPseudoephedrine
Can raise blood pressure and heart rateSpironolactone
Potassium can build upSulfamethoxazole-trimethoprim
Potassium can build up
Minor 12 interactions
Additive blood pressure loweringAtenolol
Additive blood pressure loweringCarvedilol
Additive blood pressure loweringClonidine
Additive blood pressure loweringFurosemide
Additive blood pressure loweringHydrochlorothiazide
Additive blood pressure loweringMetoprolol
Additive blood pressure loweringPropranolol
Additive blood pressure loweringSildenafil
Small extra drop in blood pressureTadalafil
Small extra drop in blood pressureTamsulosin
Additive blood pressure loweringTizanidine
Additive blood pressure lowering
No known interaction found
Our rules found no interaction between Losartan and: Acetaminophen, Acyclovir, Albuterol, Alcohol, Allopurinol, Alprazolam, Amitriptyline, Amoxicillin, Amoxicillin-clavulanate, Amphetamine salts, Apixaban, Aripiprazole, Ashwagandha, Atorvastatin, Azithromycin, Baclofen, Birth control pills, Bismuth subsalicylate, Buprenorphine-naloxone, Bupropion, Buspirone, Caffeine, Calcium carbonate, Cannabis, Cephalexin, Cetirizine, Ciprofloxacin, Citalopram, Clindamycin, Clonazepam, Clopidogrel, Codeine, Colchicine, Creatine, Cyclobenzaprine, Dextromethorphan, Diazepam, Digoxin, Diphenhydramine, Doxycycline, Doxylamine, Duloxetine, Empagliflozin, Escitalopram, Esomeprazole, Estradiol, Famotidine, Fexofenadine, Finasteride, Fish oil, Fluconazole, Fluoxetine, Gabapentin, Glipizide, Grapefruit juice, Guaifenesin, Hydrocodone, Hydroxychloroquine, Hydroxyzine, Insulin, Iron supplements, Isotretinoin, Kratom, Lamotrigine, Levetiracetam, Levofloxacin, Levothyroxine, Lisdexamfetamine, Loperamide, Loratadine, Lorazepam, Magnesium, Meclizine, Melatonin, Metformin, Methocarbamol, Methotrexate, Methylphenidate, Methylprednisolone, Metronidazole, Mirtazapine, Montelukast, Morphine, Naltrexone, Nicotine, Nitrofurantoin, NyQuil, Omeprazole, Ondansetron, Oseltamivir, Oxycodone, Pantoprazole, Paroxetine, Paxlovid, Phentermine, Pravastatin, Prednisone, Pregabalin, Probiotics, Promethazine, Quetiapine, Rivaroxaban, Rosuvastatin, Semaglutide, Sertraline, Simvastatin, St. John's wort, Sumatriptan, Tirzepatide, Topiramate, Tramadol, Trazodone, Turmeric, Valacyclovir, Venlafaxine, Vitamin D, Warfarin, Zinc, Zolpidem.
Add at least two medicines, supplements or alcohol.
Sources
Source: FDA label for Losartan on DailyMed (effective 2026-08), plus the labels of each interacting medicine.
This list covers the 147 medicines and substances in our database. It is not a complete list of every possible interaction. Always tell your doctor and pharmacist about every medicine, supplement and herbal product you take.