Generally, all branches of service should follow DOD Directive 6130.3, "Medical Standards for Appointment, Enlistment or Induction in the Military Services." According to the policy, you might be able to join if you haven't taken more than one dose of medication for the disorder daily, or haven't been prescribed medication more than "24 cumulative months" after you turned 14. You must also prove that, after age 14, you maintained a 2.0 grade point average during times you weren't taking medication. If you followed an individualized education plan in public school, you must show that it stopped prior to age 14. You must have no history of comorbid mental disorders.