Sildenafil citrate usually expires about 4 hours after taking it. This product is used for the treatment of male sexual dysfunction a drug that can improve the quality of male sexual life, through its special chemically active action, so that the blood vessels of the penis undergo dilation, so that the arterial sinus of the cavernous body of the penis is congested with blood, and this action can help the penis erection. Possible adverse reactions include shock, weakness, pain, arrhythmia, hypotension, and transient localized ischemic shock. It is important to note that patients taking any dosage form of nitrate, either regularly or intermittently, should not take this product. Therefore, this product needs to be taken under the guidance of a doctor, do not blindly use the drug on your own. In addition, it is recommended that patients should eat some animal kidneys in moderation, eat more beef, eggs and milk, jujube, wolfberry and other nutritious and nourishing effect of food, to avoid too much intercourse, and actively participate in physical exercise, which is good for the treatment of erectile dysfunction.