I was prescribed Amitriptyline for depression. I was also suffering from insomnia as a result of the depression and this was the deciding factor in my GP giving me this drug.

At first I was started out on a low dosage, 25mg daily, to be taken in the morning. In order for this drug to be effective one must build up the dosage over a period of a time as it is incredibly easy and dangerous to overdose on it.

Every couple of weeks I would return to my doctor for a new prescription for the higher dosage, which would usually go up by 25mg each time. After taking the medication for a very short time I noticed some side effects. The most irritating of which was the dry mouth. My tongue constantly felt like sandpaper and I had to carry everywhere, two bottles of water for me to sip, to be refilled frequently. As a result of this I had to visit the ladies room far more often than normal, which irritated me even more. The dry mouth wasn't just dry though, it hurt like hell. I had to sit with my mouth open and tongue sticking out for some sort of relief which got more than a few strange looks. Talking was difficult, frustrating and painful.
Another side effect (which is the main reason I was given Amitriptyline) was extreme drowsiness. Before, I would usually go for a whole week getting roughly 15 hours sleep. On Amitriptyline, I felt sedated and almost narcoleptic. I would visit friends and fall asleep an hour or so after arriving, I lay down on the floor to cuddle my dog once and awoke 3 hours later. This was happening on a 100mg a day dosage and my psychiatric nurse informed me that for me to feel any real benefit, my dosage would most likely have to be doubled.

I was quiet distressed by this, I was already clinically depressed and now I had a mouth drier than a camel's arse and felt perpetually exhausted and sleepy, to the point of sleeping through shifts at work.
I kicked up shit with my doctor and was eventually prescribed fluoxetine and temazepam, ahh, good old prozac!

WARNING!
If you are ever prescribed this drug; never, ever under any circumstances drink alcohol while on it! In my foolish teenage rebelious nature I decided to ignore the warning on the packet, very bad idea. It magnified all the worst feelings I'd ever felt and slapped me with it all at once in full force. I felt more suicidal and drunk than ever before and did some very stupid things while in this state. I was lucky though, I had people around to look after me and stop me from doing something I would really regret.