Pemoline, sold under the brand name Cylert among others, is a stimulant medication which has been used in the treatment of attention-deficit hyperactivity disorder (ADHD) and narcolepsy. It has been discontinued in most countries to due to rare but serious problems with liver toxicity. The medication was taken by mouth. Side effects of pemoline include insomnia, decreased appetite, abdominal pain, irritability, and headaches. Rarely, the medication can cause serious liver damage, and this can result in liver transplantation or death. Pemoline is a psychostimulant and acts as a selective dopamine reuptake inhibitor and releasing agent. Hence, it functions as an indirect agonist of dopamine receptors. Pemoline has little effect on norepinephrine and hence has minimal or no cardiovascular or sympathomimetic effects, in contrast to many other stimulants. Pemoline was synthesized in 1913 but was not discovered to be a stimulant until the 1930s and was not used in the treatment of ADHD until 1975. It was withdrawn due to liver toxicity in many countries between 1997 and 2005, including the United States. However, it remains available in Japan for the treatment of narcolepsy at lower doses than used for ADHD. Pemoline is a schedule IV controlled substance in the United States due to its relation to other stimulants and a potential for misuse. It seems to have less misuse potential than other stimulants. Medical uses Pemoline has been used in the treatment of ADHD and narcolepsy. It has also been used in the treatment of excessive daytime sleepiness. The medication was typically used at doses of 18.75 to 112.5mg once per day in the treatment of ADHD, with the effective dose for most people being in the range of 56.25 to 75mg. The onset of action of pemoline is gradual and therapeutic benefits may not occur until the third or fourth weeks of use. This may be due to a cautious low initial starting dose of 37.5mg and gradual titration in dose upwards over several weeks. Available forms Pemoline was available in the form of 18.75, 37.5, and 75mg oral immediate-release tablets (Cylert) as well as 37.5mg oral immediate-release chewable tablets. It was provided mainly in the form of the free base but also as the magnesium salt. Side effects Side effects of pemoline include insomnia, decreased appetite, abdominal pain, irritability, and headaches. It has minimal cardiovascular or sympathomimetic side effects. Pemoline is described as a lower-efficacy/milder stimulant than classical