Hi
I was on Amitriptyline for pain relief for 15 years, and it really gave me back my life when I was ill.
It's indicated for nerve related pain, and sciatica is pain arising from the sciatic nerve, so it should work very well. It works by blocking the pain impulses before they reach the brain, so the nerve still fires but the brain doesn't receive it.
You shouldn't need any other pain meds once it's had a chance to kick in, after about 3 weeks. Having said that, I slept for most of the first 3 weeks (I hadn't slept properly because of the pain for a couple of years!). I'd been taking DF118 (dihydrocodeine) and had reached 16 a day, with the pain not being touched. The codeine had got me hooked, and I had to come off them gradually. I think it took me about 4 months to stop taking it. (I've still got the bottle just in case!)
It should work very well with sciatica. Good luck with it!