Ritalin is a stimulant for the central nervous system. It does so by enhancing hyperactivity and impulse control. This drug is essentially used to treat cases of ADHD and narcolepsy. Its pill is two sided with both the sides filled with different compounds. In one half are the release beads while the other half is enteric-coated that contain the delayed release beads. This design enables the pill to first release methylphenidate and after a small interval of time; it releases the second doze of the same compound. This drug must not be taken by a person who has glaucoma, an overactive thyroid, severe high blood pressure, tics or Tourette’s syndrome, angina, history of heart failure, heart rhythm disorder, one who had had a rennet heart attack, a hereditary condition of say, fructose intolerance, glucose-galactose malabsorption, sucrose-isomaltase deficiency, severe anxiety, tension or agitation. This drug may also pose addiction risks to those who have had a history of drug abuse. Therefore, Ritalin should be taken in very small quantities and only as prescribed to you. Moreover, this drug impairs your thinking and reactivity temporarily and so impulsive activities should be avoided right after taking this.