I'm back at that stage in my medication cycle where 40mg of dexamphetamine is no longer enough to keep me alert, or even awake, for a full 16 hours and I have to decide whether to compensate with caffeine or take a break from the dexamphetamine. I'm going to have a sleep study done at some point in Jan/Feb, and the neurologist who's assessing me is keen to switch me from dexamphetamine to modafinil, which is reputed to be free from the tolerance issues that force me to take frequent breaks from dexamphetamine. I'm curious about modafinil, but also apprehensive about coming off of dexamphetamine, since the dexamphetamine has a nice assortment of benefits besides just keeping me awake and I wouldn't like to lose those other benefits.