Did he write it in the end, right as you were going out the door without any discussion or did you all discuss this? I wouldn't necessarily fill it if you disagree and/or don't feel you need it. But I wouldn't not take it just because of the weight gain, either. If you have a good relationship with your pharmacist, I'd talk with them too, not to "overturn" or second-guess your pdoc but just to get a different perspective. I don't know how your body image is and where weight interacts with your mental health too. Do you have a T? Get a bunch of input from people you know and trust and then make your own decision. It's your health and life but I don't think the pdoc wrote it just to be mean and make you gain weight?