Thanks to everyone who answered me. My son is just on Mestinon but he also takes Gabapentin which is seizure medication. I am going to talk to his neurologist next week and see if that might be it. He takes that for the feeling that he has all the time wanting to pull and stretch his muscles. If he doesn't take that he goes crazy with that sensation that he feels all the time. The Gabapentin helps that but it might be what is causing the memory loss. We will see. Thanks so much for everything.