Does anyone know anything about the effects of medications on certain liver enzymes? I have taken paxil, which is said to inhibit the cytochrome p 450 enzyme. This enzyme is responsible for phase I metabolism in the liver. I gained weight while on the drug, and have been off for 6 months. I have not been able to lose any weight despite diet and exercise. Could this enzyme inhibition be the cause? What could I do? I was considering going to a homeopathic practitioner. I don't think that a regular MD would know much about this.