Why Pharma site considired as bad Neighborhoods in Can hurt you serp if you get link from them , i thing pharmacy sites does not provide any illegal content or something like that just shopping and general drugs information why they are considered as bad Neighborhoods in google eyes !
A legit pharma site these days is probably only going to be one that's either the original manufacturer or the govt. Maybe a handful of sites that have built authority over many years. But that's about it.
Pharma niche is tabu mainly because there is a lot of web spam around it. Back into 2007 and ever since spammers usually promot shops selling pills,drugs and blast all the web with spam backlinks to this kind of sites. Considering that there is also a high percentage of fraud and illegal (read not licensed) activities isn't hard to guess why Google looks with thin eyes on pharma sites.