I used to take ketipinor (which is antipsychotic medication, they still use that as sleep aid in my country even though it's not reccomended) for my severe sleep problems and while it helped me to sleep it made my stutter SO much worse. It was especially hard to speak about half an hour after I had taken it, almost impossible (my speech was also slurred, it sounded like I was very drunk) so I Learned to just go to bed immediately after I had taken it and not bother having conversation with anyone before going to bed.