marijuana and medication

my doctor has me on premarin prometrium for amenorrhea. will smoking marijuana have an effect?

[Machelle Seibel, MD]

Marijuana has a number of effects on the body. In premenopausal women it can disrupt menstual cycles and in men it can separate sperm heads and tails.
There are over 400 hundred different chemicals in marijuana, about 60 of which are known as cannabinoids. These chemicals are found nowhere else in nature. The most important cannabinoid in marijuana is a known as delta-9 tetrahydrocannabinol (THC). THC is the main psychoactive (mind-altering) ingredient in marijuana.

Several studies show that some of the substances in marijuana bind to the estrogen receptor. That is the key that unlocks the effects of estrogen in the body and means marijuana prevents some of the Premarin from attaching to those receptors and therefore prevents if from being as effective.  At the same time, marijuana has its own estrogen effect. Marijuana also varies from lot to lot and is not consistent as a substance. Bottom line, marijuana will have an effect on your body while taking Premarin and Prometrium. The exact extent is difficult to say because marijuana isn't a legal substance and varies each time it is consumed. Best decision is either to stop using it or discuss it openly with your doctor and test the estrogen effect to see how it is affecting you.
Machelle M. Seibel, MD