I've tried draino and also the bleach techniqe however neither of them works but in addition to the shower whenever I flush my toilet I get the same odor.I live in a basement and while I am not sure what the technical terms are I think I have a direct vent to the sewer in my bathroom so there is no doubt that some smell comes from there but whenever I turn the shower on I definitely get the smell coming from my shower drain.

I've tried draino and also the bleach techniqe however neither of them works but in addition to the shower whenever i flush my toilet i get the same odor.I live in a basement and while i am not sure what the technical terms are i think i have a direct vent to the sewer in my bathroom so there is no doubt that some smell comes from there but whenever i turn the shower on i definitely get the smell coming from my shower drain.

What I think's happening here is a partial blockage that as the discharge hits it sends a bubble of sewer gas back through the shower trap. The answer is to remove the strainer and snake out the drain. Put enough out to get in the toilet main and snake that also. Afterwards, flush the shower line with boiling water. Good luck, Tom