Trocer 400 mcg/Spray is a sublingual spray manufactured by Incepta Pharmaceuticals Ltd., containing Nitroglycerin (also known as Glyceryl Trinitrate) as its active ingredient. It is primarily used for the acute relief and prophylaxis of angina pectoris due to coronary artery disease. Each metered spray delivers 400 micrograms of Nitroglycerin, which acts as a vasodilator to relax vascular smooth muscle, leading to the dilation of both arteries and veins. This action reduces the heart's workload by decreasing venous return and systemic vascular resistance, thereby alleviating chest pain associated with angina.