The first psychiatric medication I ever took was amitriptyline. This was well before I was diagnosed with bipolar or even major depression - it was prescribed when I was diagnosed with fibromyalgia, which was apparently caused by my terrible sleep difficulties. For the first time in 20 years I slept soundly through the night and woke up rested. It was glorious... BUT...
I kept developing a tolerance to it and having to increase the dose. I started at 5 mg and wound up at 65. My appetite increased substantially, in a few years I had gone from 135 pounds to 165. I couldn't tolerate the extra weight and stopped taking it. And back came the sleep problems.
A few years later I went into the worst depression of my life. I'd lost all the weight and ten pounds more. At that point I was put on Prozac. I had a year of delicious mild hypomania... and then the effect tapered off and I gained about 20 pounds.
With Prozac no longer working, I went to a new GP (I'd moved) who prescribed Serzone (nefazodone). That was a disaster because the guy had me start at full dose, which isn't supposed to be done, and the side effects were awful.
Finally I found a psychiatrist who diagnosed bipolar disorder. From then on I've gone through dozens of medication changes - and have kept gaining weight.
Mood stabilizers - Depakote, Topamax and finally Lamictal; antidepressants - Celexa, Trazodone (which I've stayed on for a long time), Lexapro, Paxil, finally Cymbalta (probably others I've forgotten). Trazodone helps me sleep, so it's important.
Other sleep/anxiety meds: Ativan and Ambien - but I got so horribly addicted to Ativan that I won't take any benzodiazepine long-term again. The withdrawal is too dreadful. Now I can take Klonopin when I really need it, but I avoid it most of the time.
Antipsychotics: Geodon and Seroquel. Seroquel really helps me with both mood and sleep - but I'd already gotten up to 165 pounds when I started it, and ballooned clear up to 205. For someone who was comfortable at 125-135 pounds, that's miserable.
I now take a minimum dose of Seroquel - just 20 mg - but still struggle with weight problems. Using a food and exercise diary, I lost almost 35 pounds from 2007 to 2008, but when extreme stress plunged me into black depression with days of hypomania here and there, I stopped tracking and haven't gone back to it yet. I've gained back 15 pounds.
Sometimes I wonder what would happen if I went off everything except Trazodone and Seroquel - the two meds I need for sleep. Has my body adjusted too much to being way overweight by now, or would I lose weight without all the other meds? Honestly - I'm so sick of being fat that there are times I feel I'd rather be more moody.
But I don't think I'd feel the same way if I crashed into depression again. Sigh.