You should be taking the sertraline daily if it was prescribed. Taking a day off of it isn't going to minimize any risks for serotonin toxicity. One thing to be careful with when using methamphetamine while on serotonergic anti-depressants (other than serotonin toxicity) is not doing so much you go into psychosis. Up until recently I was shooting meth, because the initial rush would kill my pain for 30 minutes to an hour. I was taking the maximum dose of amitriptyline at the time (300mg daily). The combination of the Elavil and shooting 1/3 - 1/2 a gram at a time would make me go into psychosis after the initial rush and I would have the most realistic hallucinations. Was not fun.
