That's probably it. I tasted, okay fine, slurped, this guy's cum and I tasted some herbaceous notes to it. During our cuddle session he asked me how his cum tasted like and after I mentioned what it tasted, he then confessed that he smokes weed every day. Still did not get high from that session though.
I guess, to the earlier point, should a client as a precautionary measure, mention to the provider about any severe allergies they may have?