Methamphetamine is commonly known as speed, meth, and chalk. In its smoked form, it is often referred to as ice, crystal, crank, and glass. It is a white, odorless, bitter-tasting crystalline powder that easily dissolves in water or alcohol. The drug was developed early last century from its parent drug, amphetamine, and was used originally in nasal decongestants and bronchial inhalers. Like amphetamine, methamphetamine causes increased activity and talkativeness, decreased appetite, and a general sense of well being. However, methamphetamine differs from amphetamine in that at comparable doses, much higher levels of methamphetamine get into the brain, making it a more potent stimulant drug. It also has longer lasting and more harmful effects on the central nervous system.