 the therapeutic mechanism of action of modafinil for narcolepsy and sleep-wake disorders remains unknown.Modafinil acts as an atypical, selective, and weak dopamine reuptake inhibitor which indirectly activates the release of orexin neuropeptides and histamine from the lateral hypothalamus and tuberomammillary nucleus, respectively all of which may contribute to heightened arousal.Research found that modafinil elevates histamine levels in the hypothalamus in animals.