insomnia
"Generic doxepin (25mg) helped wonderfully with my insomnia...at first. It's great for short-term use because it truly lets you sleep *as long as you want*.  However after about 3 weeks, I starting developing tolerance and began taking 50mg every night.  A month later and I was up to 75mg.  In months 4 and 5, I was taking 100mg every night.  With the increased dosage, so increased the unpleasant side effects ("hangovers" in the morning).  When I switched to a stronger sedative, I suffered withdrawal in the form of middle-of-the-night awakenings for several weeks.

One other note - it's not fast acting like newer drugs so I had to take it 2 hours before bedtime in order to feel sleepy."