HRH3 and narcolepsy: H3Rs are considered a promising target for the development of drugs to treat hypersomnia and H3R antagonists have been shown to promote wakefulness and counteract narcolepsy in animal models.12 The observation that, in experimental parkinsonism, thioperamide restores normal motor activity during the active phase of the circadian rhythm indicates the potential efficacy of this drug for the treatment of sleepiness and reduced wakefulness in PD patients.