Methamphetamine is a strong central nervous system stimulant that is mainly used as a recreational drug. Methamphetamine approved by the United States Food and Drug Administration under the trade name Desoxyn for attention deficit hyperactivity disorder and obesity in adults and children, and is sometimes prescribed off label for narcolepsy and idiopathic hypersomnia. it should not be used by heart patients specially if the heart function is sub optimal as there is increase chances of life-threatening arrythmia which may cause sudden cardiac death. also there are chances of recurrent de-compensation and hospitalization he should go for cognitive behavior therapy to stop Methamphetamine. all the best.