As well they should. It is a legal product and she has a prescription for it.
If he personally doesn't want to fill the prescription he can give it back to her and she can take it to someone who will. Just when did he suddenly acquire the right to steal her property? When did he acquire the right to make moral judgements for her?
Woah, guys, you're starting to use the same sorts of arguments that pro-abortion people use. Better watch that, now.