Nitroglycerin should not normally be applied to the penis. Nitroglycerin belongs to the vasodilator class of drugs and is mainly used for the prevention and treatment of coronary heart disease, angina pectoris, hypertension, congestive heart failure and other conditions. Adverse reactions such as vasodilatory headache and dizziness, nausea and vomiting, palpitations and sweating may occur after using this product. As can be seen from the indications for this product, it has no efficacy in treating penile disorders, so it should not normally be applied to the penis. This product is prohibited for use in patients with acute circulatory failure, myocardial infarction with low filling pressure, hypertrophic obstructive cardiomyopathy, cerebral hemorrhage or head trauma, constrictive pericarditis, pericardial tamponade, severe hypotension (systolic blood pressure of 90mmHg), hepatic and renal impairment, anemia, glaucoma, and increased intracranial pressure; and is prohibited in patients who are allergic to nitro compounds. If patients have penile disease, it is recommended to go to a regular hospital, under the guidance of the doctor, to identify the cause and target treatment.