Denying a woman access to birth control (and yes, that’s what abortion is) is an act of bigotry and aggression. Providing the state with poison to kill someone is also an act of aggression. And both undercut trust and respect of the profession; if someone is willing to forbid a woman contraception to “punish the slut”, why wouldn’t they be willing to quietly replace an AIDS patients antiviral drugs with something that doesn’t work to punish them? They’ve already demonstrated that what matters to them is their bigotry, not their profession.
People in a medical profession shouldn’t use their position to harm people; it undercuts the trust that lets the institution of medicine function. Therefore, pharmacists should neither provide poison to kill the victims of the death penalty, nor should they be allowed to torment women because some book of Iron Age mythology tells them to.