Sulfamethoxazole-trimethoprim interactions
Overview
Sulfamethoxazole-trimethoprim (Bactrim, Septra) is a sulfa antibiotic combination. In our database it has 9 known interactions with common medicines and substances: 2 serious, 6 that need caution and 1 minor.
Avoid / serious 2 interactions
Use caution 6 interactions
Low blood sugar riskInsulin
Low blood sugar riskLisinopril
Potassium can build upLosartan
Potassium can build upPotassium supplements
Potassium can build upSpironolactone
Potassium can build up
Minor 1 interaction
No known interaction found
Our rules found no interaction between Sulfamethoxazole-trimethoprim and: Acetaminophen, Acyclovir, Albuterol, Alcohol, Allopurinol, Alprazolam, Amitriptyline, Amlodipine, Amoxicillin, Amoxicillin-clavulanate, Amphetamine salts, Apixaban, Aripiprazole, Ashwagandha, Aspirin, Atenolol, Atorvastatin, Azithromycin, Baclofen, Birth control pills, Bismuth subsalicylate, Buprenorphine-naloxone, Bupropion, Buspirone, Caffeine, Calcium carbonate, Cannabis, Carvedilol, Celecoxib, Cephalexin, Cetirizine, Ciprofloxacin, Citalopram, Clindamycin, Clonazepam, Clonidine, Clopidogrel, Codeine, Colchicine, Creatine, Cyclobenzaprine, DayQuil, Dextromethorphan, Diazepam, Diclofenac, Digoxin, Diphenhydramine, Doxycycline, Doxylamine, Duloxetine, Empagliflozin, Escitalopram, Esomeprazole, Estradiol, Excedrin, Famotidine, Fexofenadine, Finasteride, Fish oil, Fluconazole, Fluoxetine, Furosemide, Gabapentin, Grapefruit juice, Guaifenesin, Hydrochlorothiazide, Hydrocodone, Hydroxychloroquine, Hydroxyzine, Ibuprofen, Iron supplements, Isotretinoin, Kratom, Lamotrigine, Levetiracetam, Levofloxacin, Levothyroxine, Lisdexamfetamine, Lithium, Loperamide, Loratadine, Lorazepam, Magnesium, Meclizine, Melatonin, Meloxicam, Metformin, Methocarbamol, Methylphenidate, Methylprednisolone, Metoprolol, Metronidazole, Mirtazapine, Montelukast, Morphine, Naltrexone, Naproxen, Nicotine, Nitrofurantoin, NyQuil, Omeprazole, Ondansetron, Oseltamivir, Oxycodone, Pantoprazole, Paroxetine, Paxlovid, Phentermine, Phenylephrine, Pravastatin, Prednisone, Pregabalin, Promethazine, Propranolol, Pseudoephedrine, Quetiapine, Rivaroxaban, Rosuvastatin, Semaglutide, Sertraline, Sildenafil, Simvastatin, St. John's wort, Sumatriptan, Tadalafil, Tamsulosin, Tirzepatide, Tizanidine, Topiramate, Tramadol, Trazodone, Turmeric, Valacyclovir, Venlafaxine, Vitamin D, Zinc, Zolpidem.
Add at least two medicines, supplements or alcohol.
Sources
Source: FDA label for Sulfamethoxazole-trimethoprim on DailyMed (effective 2026-07), 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.