Adderall is a prescription medication that acts as a central nervous system stimulant. It's best known for treating Attention-Deficit Hyperactivity Disorder (ADHD), a condition that can make it hard to focus, control impulsive behaviors, or manage activity levels.

For individuals with ADHD, Adderall can improve focus and reduce impulsivity and hyperactivity, making it easier to manage daily tasks at school, work, or home. It's also prescribed for narcolepsy, a sleep disorder characterized by overwhelming daytime sleepiness and sudden attacks of sleep.

Adderall isn't a single chemical. It's a brand name for a combination of four different amphetamine salts. These are mixed isomers of amphetamine, a potent central nervous system stimulant.

The specific blend is designed to provide a steady and lasting effect. The immediate-release version of the drug contains equal parts of these four salts.

These salts break down into two active ingredients: dextroamphetamine and levoamphetamine. Dextroamphetamine is the more powerful of the two in terms of its effects on the brain. Levoamphetamine is slightly less potent on the brain but has a more noticeable effect on the cardiovascular system and tends to last longer. Combining them is intended to create a balanced therapeutic effect.

The story of Adderall begins with a different drug called Obetrol, which was marketed in the 1950s as a weight-loss medication. The original formula for Obetrol was a mix of several amphetamine salts, including methamphetamine.

Over the years, the formulation of Obetrol changed, and eventually, the rights to the drug were sold to a small pharmaceutical company called Rexar. In the 1990s, another company, Richwood Pharmaceuticals (which later became part of Shire), bought Rexar. They saw potential in the drug not for weight loss, but for ADHD.

Richwood decided to reformulate Obetrol. They removed the methamphetamine and adjusted the remaining amphetamine salts to create the four-salt combination we know today. They rebranded this new formulation as Adderall, a name derived from "A.D.D. for All."

After conducting clinical trials, the company sought and received approval from the U.S. Food and Drug Administration (FDA). In 1996, Adderall was officially approved to treat ADHD in children, and approval for adults followed a few years later. This marked its transition from an obscure diet pill to one of the most widely recognized treatments for ADHD.