Try changing medication, although they're nearly all slightly different forms of amph, the differences are significant. For me, ritalin is just headaches, modafinil is less effective but wonderfully free of most side-effects, and dex is the most useful thing I can legally get.

Unfortunately modafinil is almost 10x the price of dex in Australia if you don't have narcolepsy, and the drug that I suspect would benefit me the most (adderall, a mix of dex and meth) is simply illegal.