Timothy syndrome, a rare autosomal-dominant disorder, is characterized by presence of a heart arrhythmia (long QT syndrome), which causes the cardiac muscle to take longer than usual to recharge between beats and can result in sudden death. Now scientists at Columbia University have discovered that a common FDA-approved over-the counter cough suppressant, dextromethorphan, can shorten the prolonged QT intervals in both cellular and mouse models of TS.