The Nootropic modafinil is recommended to relieve excessive daytime sleepiness. A small minority of users (about 0.27%) have, however, claimed to grind their teeth. Because the nootropic stimulates the sympathetic nervous system, it may cause teeth grinding. Read this blog post on modafinil teeth grinding for more information.The Nootropic modafinil is recommended to relieve excessive daytime sleepiness. A small minority of users (about 0.27%) have, however, claimed to grind their teeth. Because the nootropic stimulates the sympathetic nervous system, it may cause teeth grinding. Read this blog post on modafinil teeth grinding for more information.