Could a acne pill stop your growth?

Yes: Isotretinoin is believed to be capable of stopping the growth of long bones if the patient has not achieved his/her full height. This is something to consider in prescribing it. Most acne can be managed either with topical benzoyl peroxide alone, or if more severe or on the trunk, adding a second rx such as systemic tetracycline or any of several others that won't stop growth.