METHYLPHENIDATE belongs to a group of medicines called 'central nervous system stimulant' used to improve wakefulness in adult patients with attention deficit hyperactivity disorder (ADHD) (overactive and short attention span) and narcolepsy (excessive and uncontrollable daytime sleepiness). ADHD is a chronic condition that mainly affects the child's behaviour , in which a child faces difficulty in paying attention or face hyperactivity (moving constantly), and impulsivity (rapid action). Narcolepsy is a medical condition in which a person faces excessive daytime sleepiness and face sleep attacks that make a person fall asleep suddenly in inappropriate situations.