What were you given and how long where you on it? Side effects should wear off after a week or 2 but if you can't handle the side effects then go back and speak to your GP. There are a lot of meds out there that they can try you with and one of those may suit you better. Unfortunately it's trial and error I'm afraid, it's taken me 12 years to find a medication that comes close to working for me, duloxetine was awful. I didn't even last 2 weeks on that as it made me feel so ill.