Prenylamine (Segontin) is a calcium channel blocker of the amphetamine chemical class that was used as a vasodilator in the treatment of angina pectoris.

Prenylamine was introduced in the 1960s by German manufacturer Albert-Roussel pharma gmbh,[1][2] which was acquired by Hoechst AG in 1974 and which in turn became part of Sanofi Aventis in 2005.

It was withdrawn from market worldwide in 1988 because it caused QT interval prolongation and torsades de pointes, greatly increasing the risk of sudden death.

[1] Prenylamine has two primary molecular targets in humans: calmodulin and myosin light-chain kinase 2, found in skeletal and cardiac muscle.

It demonstrates beta blocker–like activity that results in reduction of heart rate but shows an opposing effect on tracheal tissue response.