Enzyme | Medication Examples | Effect/Recommendation |
CYP3A4 Substrates | Immunosuppressants, chemotherapeutics, antidepressants, antipsychotics, opioids, benzodiazepines, z-hypnotics, statins, calcium channel blockers, etc. | Increased risk of side effects related to substrate. Avoid co-administration, reduce substrate dose, monitor for adverse effects, and toxicity. Avoid prescribing cascade with new treatments for side effects. |
CYP3A4 Inhibitors | Strong: Protease inhibitors, ketoconazole, loperamide, nefazodone. Moderate: Amiodarone, verapamil, cimetidine, aprepitant, imatinib. | Increased CBD bioavailability, possible increase in adverse effects. Reduce CBD dose. |
CYP3A4 Inducers | Strong: Enzalutamide, phenytoin. Moderate: Carbamazepine, topiramate, phenobarbital, rifampicin, efavirenz, pioglitazone. | Decreased CBD dose availability, possible decrease in CBD effectiveness. Increase CBD dose. |
CYP2C19 Substrates | Antidepressants, antiepileptics, proton pump inhibitors, clopidogrel, propranolol, carisoprodol, cyclophosphamide, warfarin. | Increased risk of side effects related to substrate. Avoid co-administration, reduce substrate dose, monitor for adverse effects and toxicity. Avoid prescribing cascade with new treatment for side effects. |
CYP2C19 Inhibitors | Strong: Fluvoxamine, fluoxetine. Other: Proton pump inhibitors, cimetidine, ketoconazole, clopidogrel, fluconazole, efavirenz. | Increased CBD bioavailability, possible increase in risk for adverse effects. Reduce CBD dose. |
CYP2C19 Inducers | Rifampin, carbamazepine, phenobarbital, phenytoin, St. John’s Wort. | Decreased CBD bioavailability, possible decrease in CBD effectiveness. Increase CBD dose. |
CYP2C8/9 Substrates | Rosiglitazone, buprenorphine, montelukast, celecoxib, sulfonylureas, losartan, naproxen, phenobarbital, phenytoin, rosuvastatin, valsartan, warfarin. | Increased risk of side effects related to substrate. Avoid co-administration, reduce substrate dose, monitor for adverse effects and toxicity. Avoid prescribing cascade with new treatment for side effects. |