Methamphetamine molecule. Computer graphic of the drug methamphetamine (formula C10.H15.N), a quicker acting and longer lasting derivative of amphetamine. The atoms (spheres) are colour-coded: carbon (yellow), nitrogen (blue) and hydrogen (white). Methamphetamine is synthetically produced, and often taken as an illegal stimulant. It acts on the central nervous system, alleviating fatigue and producing a feeling of mental alertness and well-being. It is now of limited use medically, due to side effects such as dependence and causing psychotic states.