I've been taking the stuff from about age 16- now 23. The first 5 years it was on and off like I would just stop taking it for a few weeks at a time. But for the past 2 years I have been taking a half yellow bar which is 1mg every single day. Well I took my last one today and I may not be able to get any more until another day or two..... I hope I don't have a seizure.