I just got back from seeing my counselor. I asked her about this and she said that medication does not interfere in a good or bad way with alters from Dissociative Identity disorder. medication has no effect on alters of DID which is why they don't prescribe medication for DID. They do sometimes prescribe medication to rule OUT DID because if the voices and acting out stops then they know the person has a different disorder ie bipolor, schizophrenia, borderline personality disorder and such where hallucinations are a symptom. Sometimes people mistake having hallucinations for having alters especially with so many on line and real time resourses out there that people use to self diagnose and then go to a therapist saying they have DID or other disorders so one of the ways that the agency uses to find out if the person self diagnosing is correct when they say they have DID is to prescribe medication and then follow up on the persons reactions to the medications.