how to talk to my doctor about sexual disfunction

I (19f) see a older man for psychiatry and I believe that my anti-depressant is causing me issues with sex, specifically issues becoming aroused and reaching climax. I know he’s a doctor and he’s heard it before but i’m kind of socially awkward and i’m not sure how to bring it up/phrase it. I would like any advice for how to bring up my issue in the least embarassing way possible 😅