Any one of a class of drugs that enhance the movement of potassium ions through the ion channels in cell membranes. In the case of smooth muscle cells, such as those in the walls of arteries, their sensitivity to the normal stimuli to contract is reduced. The result is relaxation of the muscle fibres and widening of the arteries. Potassium-channel activators are used for improving the blood supply to the heart muscle in angina pectoris. Possible side-effects include headache, flushing, vomiting, dizziness, and weakness. A currently available member of the class is nicorandil (Ikorel), administered orally.
Subjects: Medicine and Health.