Depends on the person and how it affects them. Generally speaking you don't want to do anything that would alter the method for SN. Adding new variables or changing things is what often leads to failure. You will have a better chance if you just follow the protocol as is. I can't speak for everyone but weed makes me nauseous, which is definitely what you don't want for SN. I know SI is terrifying but it's something you're going to have to overcome. There's not great advice for this, it's something everyone has to figure out on their own really.