depression
"This drug helped me feel much better, calm and peaceful. After taking the drug for 4-5 years, the only drawback I noted was a slightly diminished sex drive. After life improvements, I felt I was ready to quit, so I asked my doctor about quitting. He said I could simply quit.  Mistake!  At first I did not know what was going on and did not know it was related to the withdrawal.  Then, I researched it on the net, and found that to be the problem."