Despite it being touted as a "cure" for RLS, mine was FAR, far worse when I took Tramadol, and I often wonder if that was the initial cause for me as I am not quite sure if it ever happened before!
Also your GP is hopelessly out of date, quinine sulphate for this is as up to date as bloodletting and not as safe as it sounds!
Pramipexole is more the route now, but Ropiriniole is a similar type drug, bit of a sledgehammer to crack a nut though
My big improvement came from Magnesium supplementation... it had even more effect on cramping. I supplement transdermally using Magnesium citrate and my symptoms are barely there now, especially since I moved to other opiates instead of Tramadol. Might not work for you, but cheap and easy, some quote 65% of the population as being deficient in magnesium, so worth a try.
Would agree with comments on vit B12 and Vit D3 too...although if you supplement D3, I suggest also taking vitamin K2 to prevent calcium being deposited in arteries. Folate might be safest supplemented using 5-methyltetrahydrofolate though, rather then folic acid though.