Posted 1/3/2008 3:14 PM (GMT -6)
It's a bit of a myth that docs prescribe meds based on body weight. In an ideal world, yeah- but it never happens in the real world. Dosing is 90% intuition and 10% luck. Unless you're exceptionally underweight, a doc would prescribe 10-20mg XR right off the bat. IR's are a little different, but usually you see 5-10mg/dose prescribed, but multiple times a day.
And there aren't any contraindications for topiramate and d,l amphetamine salts. That said, both isomers of amphetamine lower the seizure threshold, increasing the odds that an epileptic will have a seizure. 10-20mg is on the very low end, and it's doubtful that it'd lower the threshold significantly at that dose w/ only intermittent dosing, especially with regular dosing of the topiramate (which raises the seizure threshold).
That said, taking a controlled substance that's been prescribed for someone else is illegal. Well, possession is illegal. I don't think there are any laws explicitly making use illegal. But it's a moot point since at one point you were obviously in possession. Little pedantic points.