Ca plus plus antagonist

A Ca⁺⁺ antagonist is any drug that acts by blocking the movement of Ca⁺⁺ ions into cells.

As an antianginal they reduce the amount of free intercellular calcium which slows the breakdown of ATP. The result is a more efficient and controlled contraction of the cardiac muscle[?] and vasodilation[?] which improves oxygen supply. See antianginal for more detail.