Nitroglycerin, Isosorbide dinitrate, Isosorbide mononitrate, and Molsidomine are types of nitrates used for treating angina and heart conditions. They work by dilating blood vessels to improve blood flow and reduce the workload on the heart. However, they can cause side effects such as headaches, tolerance development, rebound symptoms, reflex tachycardia, and hypotension. Patients with certain conditions like glaucoma, malabsorption syndrome, and brain hypertension should use nitrates with caution.