Sigmoid is the trade name and generic name of Nicorandil Tablets, which is used to treat angina pectoris and coronary artery disease. Nicorandil tablets belong to nitrate compounds, which have the effect of preventing the freeing of intracellular calcium ions, increasing the permeability of the cell membrane to potassium ions, dilating coronary blood vessels, sustainably increasing coronary blood flow, and inhibiting coronary artery spasm. So clinically the drug is used in the treatment of angina pectoris and coronary heart disease. The drug is used with adverse reactions such as headache, dizziness, abdominal pain, diarrhea, and fatigue. It is forbidden for patients with glaucoma; forbidden for patients with severe liver and kidney diseases; forbidden for those who are allergic to this product. Pregnant women and lactating women should be cautious. If you need to use the drug, it should be used under the guidance of a specialist.