I didn’t even realize that I have been on one called provigil/modafinil. I use it because of working the night shift. I find that my mind does not shut down even when my body gets worn out from my lack of set sleep schedule. I found that while getting a good nights rest and taking it while functioning on first shift or normal hours my ability to accomplish things is greatly enhanced with a newfound energy. I do not take it on my two off days unless I have a social obligation.