Tizanidine interactions
Overview
Tizanidine (Zanaflex) is a prescription muscle relaxant. In our database it has 50 known interactions with common medicines and substances: 8 serious, 27 that need caution and 15 minor.
Avoid / serious 8 interactions
Too much sedation and slowed breathingCiprofloxacin
Tizanidine levels can rise dangerouslyCodeine
Too much sedation and slowed breathingHydrocodone
Too much sedation and slowed breathingKratom
Too much sedation and slowed breathingMorphine
Too much sedation and slowed breathingOxycodone
Too much sedation and slowed breathingTramadol
Too much sedation and slowed breathing
Use caution 27 interactions
Alcohol adds to drowsiness and dizzinessAlprazolam
Extra drowsiness and slowed reactionsAmitriptyline
Combined drowsinessBaclofen
Combined drowsinessCannabis
Combined drowsinessClonazepam
Extra drowsiness and slowed reactionsClonidine
Combined drowsinessCyclobenzaprine
Combined drowsinessDayQuil
Can raise blood pressure and heart rateDiazepam
Extra drowsiness and slowed reactionsDiphenhydramine
Combined drowsinessDoxylamine
Combined drowsinessGabapentin
Combined drowsinessHydroxyzine
Combined drowsinessLevetiracetam
Combined drowsinessLorazepam
Extra drowsiness and slowed reactionsMeclizine
Combined drowsinessMethocarbamol
Combined drowsinessMirtazapine
Combined drowsinessNyQuil
Combined drowsinessPhenylephrine
Can raise blood pressure and heart ratePregabalin
Combined drowsinessPromethazine
Combined drowsinessPseudoephedrine
Can raise blood pressure and heart rateQuetiapine
Combined drowsinessTrazodone
Combined drowsinessZolpidem
Extra drowsiness and slowed reactions
Minor 15 interactions
Additive blood pressure loweringAshwagandha
A bit more drowsinessAtenolol
Additive blood pressure loweringCarvedilol
Additive blood pressure loweringFurosemide
Additive blood pressure loweringHydrochlorothiazide
Additive blood pressure loweringLisinopril
Additive blood pressure loweringLosartan
Additive blood pressure loweringMelatonin
A bit more drowsinessMetoprolol
Additive blood pressure loweringPropranolol
Additive blood pressure loweringSildenafil
Small extra drop in blood pressureSpironolactone
Additive blood pressure loweringTadalafil
Small extra drop in blood pressureTamsulosin
Additive blood pressure lowering
No known interaction found
Our rules found no interaction between Tizanidine and: Acetaminophen, Acyclovir, Albuterol, Allopurinol, Amoxicillin, Amoxicillin-clavulanate, Amphetamine salts, Apixaban, Aripiprazole, Aspirin, Atorvastatin, Azithromycin, Birth control pills, Bismuth subsalicylate, Bupropion, Buspirone, Caffeine, Calcium carbonate, Celecoxib, Cephalexin, Cetirizine, Citalopram, Clindamycin, Clopidogrel, Colchicine, Creatine, Dextromethorphan, Diclofenac, Digoxin, Doxycycline, Duloxetine, Empagliflozin, Escitalopram, Esomeprazole, Estradiol, Excedrin, Famotidine, Fexofenadine, Finasteride, Fish oil, Fluconazole, Fluoxetine, Glipizide, Grapefruit juice, Guaifenesin, Hydroxychloroquine, Ibuprofen, Insulin, Iron supplements, Isotretinoin, Lamotrigine, Levofloxacin, Levothyroxine, Lisdexamfetamine, Lithium, Loperamide, Loratadine, Magnesium, Meloxicam, Metformin, Methotrexate, Methylphenidate, Methylprednisolone, Metronidazole, Montelukast, Naltrexone, Naproxen, Nicotine, Nitrofurantoin, Omeprazole, Ondansetron, Oseltamivir, Pantoprazole, Paroxetine, Paxlovid, Phentermine, Potassium supplements, Pravastatin, Prednisone, Probiotics, Rivaroxaban, Rosuvastatin, Semaglutide, Sertraline, Simvastatin, St. John's wort, Sulfamethoxazole-trimethoprim, Sumatriptan, Tirzepatide, Topiramate, Turmeric, Valacyclovir, Venlafaxine, Vitamin D, Warfarin, Zinc.
Add at least two medicines, supplements or alcohol.
Sources
Source: FDA label for Tizanidine 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.