Source:
https://scmp.com/magazines/hk-magazine/article/2037604/remove-poisonHK Magazine
Remove Poison
吹水 (chui sui), v. Cantonese slang. To chat, bullshit.
“Become socially active.”
Extension of duk nam (毒男), “poison boy,” meaning a socially awkward geek.
Removing the “poison” means that someone stops being a shut-in and discovers girls, drinking etc.