Sildenafil is used for the treatment of erectile dysfunction in men and can be taken with a glass of water without the need to drink extra extra water. Sildenafil increases blood flow to the cavernous body of the penis and enhances erection, and is mainly used clinically for the treatment of erectile dysfunction in men. The product is administered by mouth and can be taken with a glass of water before sexual intercourse without additional drinking. If obvious dizziness or headache occurs after taking the drug, it can be relieved by resting as well as drinking water. Adverse reactions commonly occurring after the use of sildenafil include headache, dizziness, nausea, dyspepsia, rash, back pain, myalgia, nasal congestion, visual abnormalities, etc. It is contraindicated for those who are allergic to the product and those who take nitrate drugs. It is recommended to use the drug under the guidance of a physician according to the condition, and should not be used blindly.