Adult Son, 39 Yo, Decided To Abruptly Stop Using His

Adult son, 39 yo, decided to abruptly stop using his Lamotrigine 100 mg. He is doing this without the monitoring of a physician. He also abruptly stopped fluoxetine. He is on multiple other meds. He is very difficult with everyone. He is morbidly obese. Sleeps endless hours. Cannot get him to go to a doctor. I am very very concerned. Your opinion and recommendation will be appreciated.