THC and CBD are metabolized by CYP3A4 and CYP2C9
CBD, but not THC, is metabolized by CYP2C19
THC is a CYP1A2 inducer. Theoretically, THC can decrease serum concentrations of clozapine, duloxetine, naproxen, cyclobenzaprine, olanzapine, haloperidol, and chlorpromazine, amongst others.
CBD is a potent inhibitor of CYP3A4 and CYP2D6.
As CYP3A4 metabolizes about a quarter of all drugs, CBD may increase serum concentrations of:
CYP2D6 metabolizes many antidepressants, so CBD may increase serum concentrations of:
However, in practical terms THC and CBD are very safe to be taken simultaneously with most drugs. The most important interactions are as follows: