Cephalexin interactions
Overview
Cephalexin (Keflex) is a cephalosporin antibiotic. In our database it has 2 known interactions with common medicines and substances: 0 serious, 1 that need caution and 1 minor.
Use caution 1 interaction
Minor 1 interaction
No known interaction found
Our rules found no interaction between Cephalexin 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, 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, Glipizide, Grapefruit juice, Guaifenesin, Hydrochlorothiazide, Hydrocodone, Hydroxychloroquine, Hydroxyzine, Ibuprofen, Insulin, Iron supplements, Isotretinoin, Kratom, Lamotrigine, Levetiracetam, Levofloxacin, Levothyroxine, Lisdexamfetamine, Lisinopril, Lithium, Loperamide, Loratadine, Lorazepam, Losartan, Magnesium, Meclizine, Melatonin, Meloxicam, Metformin, Methocarbamol, Methotrexate, Methylphenidate, Methylprednisolone, Metoprolol, Metronidazole, Mirtazapine, Montelukast, Morphine, Naltrexone, Naproxen, Nicotine, Nitrofurantoin, NyQuil, Omeprazole, Ondansetron, Oseltamivir, Oxycodone, Pantoprazole, Paroxetine, Paxlovid, Phentermine, Phenylephrine, Potassium supplements, Pravastatin, Prednisone, Pregabalin, Promethazine, Propranolol, Pseudoephedrine, Quetiapine, Rivaroxaban, Rosuvastatin, Semaglutide, Sertraline, Sildenafil, Simvastatin, Spironolactone, St. John's wort, Sulfamethoxazole-trimethoprim, 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 Cephalexin 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.