bipolar medication lithium

Lithium – bipolar?
I’m supposed to start taking Lithium tomorrow along with antidepressants for my bipolar, I’ve only just been diagnosed. Obviously one of the first things I have done is checked the net for info – and what I’ve read has scared me!! Why does the DR want to give me a medication that has so many side effects when there are other meds out there? The weight gain and hair loss especially scare me, so does the fact that it may make my thinking slower and make me feel slower – I’m scared, should I not take them until I have talked things through properly with my psychiatrist as I don’t feel comfortable taking them. Have any of you had bad side effects from Lithium?
My son was given lithium for his bipolar. He did not like it and refused to take it any further because of the side effects. You pose a very very good question, WHY does your doctor give you a med that is as old as the hills with side effects as such?
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