Whats a drug you tried and hated?

Im sure plenty of people here have drugs they've done and disliked enough to never even recommend them to genuine junkies. I used to overtake mood stabilizers and the aftermath would be a massive headache and being asleep for the majority of the time (would last about a week) i continued to do it because it put me to sleep but they really sucked and often made my mind fog so i dont remember much of what i did when i did it and while i was coming down from it