Please note that this blog is not to be considered medical advice. Always consult your physician for more information and/or questions related to your specific medical history.
THC and CBD are both metabolized through the liver by the same enzymes that metabolize around 60% of the prescription medications many individuals take. That's why when taking a dose of THC or CBD with prescription meds, there could be an interaction (with CBD generally more likely to interact than THC).
A change in the dosage of the prescription medication — especially going from a very low dose to a high one — can be dangerous. Plus, taking additional medications that cause sedation can negatively interact with cannabis and amplify the sedative effect.
Sometimes reactions between cannabis and prescription drugs can be delayed depending on how the medication is metabolized. For example, the medication Gabapentin Enacarbil, a form of Gabapentin, is metabolized differently than a regular or extended-release form of Gabapentin. CBD and THC have also been shown to affect common medications like Warfarin, Theophylline, and Clobazam.
It's worth noting that opioids and cannabinoids haven’t generally been shown to have a negative interaction. Research shows that people who consume opioids and cannabis together may actually decrease their opioid doses.
YOU SHOULD ALWAYS TALK YOUR DOCTOR REGARDING YOUR PRESCRIPTION MEDICATIONS AND HOW THEY MAY INTERACT WITH CANNABIS.
Grapefruit is similar to THC and CBD because it is metabolized by the same liver enzymes as many prescription medications. Many physicians will warn a patient not to take a particular medication with grapefruit because it can affect how the medication is metabolized in their body and cause an interaction.
The following list provides some common drug categories and specific medications that have a “grapefruit” warning. While not yet fully proven, they could cause some issues if consumed with THC and/or CBD.
Amoxicillin, Penicillin Gentamicin, Tetracycline, Tobramycin, Cefalexin, Doxycycline, Ciprofloxacin, Azithromycin, Sulfamethoxazole, Augmentin, Flagyl, Amoxil, Cipro, Keflex, Bactrim, Levaquin, Zithromax, Avelox, Cleocin
Abraxane, Adriamycin, Carboplatin, Cytoxin, Daunorubicin, Doxil, Ellence, Fluoricil, Gemza, Halavan, Ixempra, Methotrexate, Mitomycin, Mitoxantrone, Tamoxifen, Taxol, Taxotere, Thiotepa, Vincristine, Xeloda
Zyrtec, Chlor-Trimeton, Benadryl, Allegra, Claritin, Alavert
Keppra, Carbamazepine, Gabapentin, Depakote, Lamotagrine, Dilantin, Topiramate Clobazam, Tegretol, Lyrica, Lamictal, Phenytoin
Lisinopril, Norvasc, Losarten, Hydrchlorothiazide, Metoprolol, Carvedilol, Furosemide, Cozaar, Clonidine, Toprol-XL, Lasix, Valsartan, Prinivil, Zestril, Coreg, Ramapril, Vasotec, Labetalol, Diovan, Lopressor, Toprol XL, Lasix, Microzide, Clopidogrel/Plavix, Warfarin/Coumadin
Lipitor/Atorvastatin, Lovastatin/Mevacor, Pravastatin/Pravachol, Rosuvastatin/Crestor, Simvastatin/Zocor, Ezitimibe/Zetia, Fenofibrate/Tricor, Gemfibrozil/Lopid
Cortisone, Prednisone, Methylprednisolone, Dexamethasone, Betamethasone, Hydrocortisone
Avanafil/Stendra, Sildenafil/Viagra, Tadalafil/Cialis, Vardenafil/Levitra
Nexium/esomeprazole, Protonix/Pantoprazole, Prevacid, Aciphex, Prilosec/Omeprazole, Zofran/Ondansetron, Promethazine, Reglan, Meclizine, Transdermal Scopolamine Patch
Amiodarone/Cardarone, Flecainide/Tambocor, Procainamide/Procan, Quinidine, Tocainide, Inderal/Propranolol
Prednisone, Cyclosporin, Neoral, Prograf, Inuran, Azathioprine, Tacrolimus
Citalopram/Celexa, Escitalopram/Lexapro, Fluoxetine/Prozac, Paroxetine/Paxil, Sertraline/Zoloft, Olanzapine/Zyprexa, Quetiapine/Seroquel, Risperidone/Risperdal, Geodon, Clozapine, Lithium, Valproic Acid, Ativan/Lorazepam, Trazadone, Ambien/Zolpidem, Clonazepam/Klonopin, Valium/Diazepam
Codeine, Fentanyl, Hydrocodone, Hydromorphone/Dilaudid, Meperidine, Oxycontin, Oxycodone, Tramadol, Norco, Vicodin, Lortab, Demerol, Percocet, Roxicet
Terazosin/Hytrin, Tamsulosin/Flomax, Silodosin/Rapaflo, Prazosin/Minipress, Doxazosin/Cardura, Alfuzosin/Uroxatol
Finally, below are several other medications that should be closely monitored when co-administered with cannabinoids because they are metabolized by similar liver enzymes and may affect how the prescription medication will work in the body.
Acenocoumarol, Alfentanil, Aminophylline, Amiodarone, Amitriptyline, Amphotericin B, Argatroban, Busulfan, Carbamazepine, Clindamycin, Clomipramine, Clonidine, Clorindione, Cyclobenzaprine, Cyclosporin, Dabigatran Etexilate, Desipramine, Dicoumarol, Digitoxin, Dihydroergotamine, Diphenadione, Dofetilide, Dosulepin, Doxepin, Ergotamine, Esketamine, Ethinyl Estradiol, Ethosuximide, Ethyl Biscoumacetate, Everolimus, Fentanyl, Fosphenytoin, Imapramine, Levothyroxine, Lofepramine, Melitracen, Meperidine, Mephenytoin, Mycrophenolic Acid, Nortriptiline, Paclitaxel, Phenobarbitol, Phenytoin, Pimozide, Propofol, Quinidine, Sirolimus, Tacrolimus, Temsirolimus, Theophylline, Thiopental, Tianeptine, Trimipramine, Valproic Acid, Warfarin, Phenprocoumon
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Disclaimer: The information in this blog post is meant for educational purposes of those 21 and over only. Medical decisions should not be made based on advertising. There may be health risks associated with consumption of this product so please consult a physician prior to use.