Nicorandil is a drug for treating angina that works similarly to nitrates by relaxing the walls of the coronary arteries to improve blood flow to the heart muscle. Nicorandil is a potassium channel activator and its UK brand name is Ikorel. Nicorandil is a twice-daily tablet generally used as a third- or fourth-line antianginal combined with a beta-blocker or a calcium channel blocker. Nicorandil is usually started on a low dose and then may be increased according to the response.

Nicorandil is usually considered safe but the vasodilatory mode of action can lead to low blood pressure (hypotension), particularly in the elderly, in dehydration, in combination with antihypertensives and other blood pressure-lowering drugs, including medication for erectile dysfunction, such as sildenafil (Viagra). Alcohol increases the effects of nicorandil. Side effects of nicorandil include nausea, flushing, palpitations, and dizziness. A relatively rare but potentially serious side effect is ulcerations in the mouth and elsewhere in the gastrointestinal system.