I am on Effexor Xr 37.5 mg which i just recently started taking. I occasionally smoke marijuana, usually at parties when i dont want to drink. The first time i tried to smoke on this drug everything was fine, until i had a cigarette. By my second puff off the cig, my hands became very sweaty, my heartrate accelerated and i got something like an electrical shock in my brain and all through the nerves in my body (lasting approx. 5-10 seconds). I soon calmed down and in about ten minutes i was fine. I just figured I shouldn't be high on the drug and have a cigarette at the same time.
Then the second time i got high on this drug, the same thing happened, only milder this time. The only difference was that it was without the cigarette.
I have narrowed this down to two possibilities.
1. Effexor is an SNRI, inhibiting the uptake of serotonin and norepinephrine. I have read elswhere that properties of the norepinephrine reuptake inhibitor can also inhibit the uptake of dopamine to a lesser degree. THC, the main active chemical in marijuana, also causes a release of Dopamine, as does nicotine. In this first scenario i thought that perhaps i had a surge of dopamine that sent my nervous system into shock.
2. Something my sister brought up. Possibly CO2 levels in my blood just raised too high and my brain, thinking it was starving for oxygen, sent me into a panic mode until the CO2 levels fell.
I have read reports of people smoking marijuana and being fine with Effexor on doses way higher than mine. I have also come across two accounts of this combination inducing a seizure.
Just wondering what anyone who has knowledge on this has to think.