What medication should i ask my doctor to prescribe for sever body/facial cystic acne that won't affect my birth control?

Isotretinoin: If you have to ask, you are probably a candidate for this rough stuff. It's not for the faint-hearted, but as a young woman in her prime, acne is a terrible personal and professional liability that you must manage. Spironolactone, antibiotics and so forth are likely to fail. I trust you are using benzoyl peroxide already. Best wishes.