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Cannabis and Prescription Medications: How to Be Safe and Responsible When Using Weed

 September 22, 2023  Written by Feel State
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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.

How Cannabis Interacts With Prescribed Medications

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). 

Generally speaking, there are a few different reactions that could occur with cannabis and prescription medications.

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.


The Grapefruit Effect in Cannabis Medicine

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. 

Antibiotics and Antimicrobials and Weed

Amoxicillin, Penicillin Gentamicin, Tetracycline, Tobramycin, Cefalexin, Doxycycline, Ciprofloxacin, Azithromycin, Sulfamethoxazole, Augmentin, Flagyl, Amoxil, Cipro, Keflex, Bactrim, Levaquin, Zithromax, Avelox, Cleocin

Anticancer Medications and Weed

Abraxane, Adriamycin, Carboplatin, Cytoxin, Daunorubicin, Doxil, Ellence, Fluoricil, Gemza, Halavan, Ixempra, Methotrexate, Mitomycin, Mitoxantrone, Tamoxifen, Taxol, Taxotere, Thiotepa, Vincristine, Xeloda

Antihistamines and Weed

Zyrtec, Chlor-Trimeton, Benadryl, Allegra, Claritin, Alavert

Antiepileptic Drugs and Weed

Keppra, Carbamazepine, Gabapentin, Depakote, Lamotagrine, Dilantin, Topiramate Clobazam, Tegretol, Lyrica, Lamictal, Phenytoin

Blood Pressure/Blood Thinner Medications and Weed

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

Cholesterol Medications and Weed

Lipitor/Atorvastatin, Lovastatin/Mevacor, Pravastatin/Pravachol, Rosuvastatin/Crestor, Simvastatin/Zocor, Ezitimibe/Zetia, Fenofibrate/Tricor, Gemfibrozil/Lopid

Corticosteroids and Weed

Cortisone, Prednisone, Methylprednisolone, Dexamethasone, Betamethasone, Hydrocortisone

Erectile Dysfunction Medications and Weed

Avanafil/Stendra, Sildenafil/Viagra, Tadalafil/Cialis, Vardenafil/Levitra

GI Medications for GERD or Nausea and Weed

Nexium/esomeprazole, Protonix/Pantoprazole, Prevacid, Aciphex, Prilosec/Omeprazole, Zofran/Ondansetron, Promethazine, Reglan, Meclizine,  Transdermal Scopolamine Patch

Heart Rhythm Medications and Weed

Amiodarone/Cardarone, Flecainide/Tambocor, Procainamide/Procan, Quinidine, Tocainide, Inderal/Propranolol

Immunosuppressants and Weed

Prednisone, Cyclosporin, Neoral, Prograf, Inuran, Azathioprine, Tacrolimus

Medications to Treat Anxiety, Depression, and Other Mood Disorders and Weed

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

Pain Medications and Weed (may increase side effects of these meds, but may also work together)

Codeine, Fentanyl, Hydrocodone, Hydromorphone/Dilaudid, Meperidine, Oxycontin, Oxycodone, Tramadol, Norco, Vicodin, Lortab, Demerol, Percocet, Roxicet

Prostate Medications and Weed

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.

Monitor the effects of these prescription medications with cannabis:

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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CBD Oil Review, Blood Pressure Medication and CBD Oil Interactions, Jason Brett, February 9, 2021

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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.

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