Viagra generally refers to sildenafil citrate tablets, and patients usually do not experience after-effects the first time 25mg, but some patients may experience adverse reactions such as facial edema and fatigue. Children, pregnant women as well as lactating women are prohibited, and allergic people are prohibited. Patients taking sildenafil citrate tablets 25mg for the first time belongs to a small dose, usually does not cause too much effect on the body, no sequelae. However, some patients may experience adverse reactions such as facial edema, fatigue, pain, chills, vomiting, muscle weakness, etc., which will usually disappear on their own after stopping the drug. Sildenafil Citrate Tablet is mainly used for the treatment of erectile dysfunction, and is not suitable for children, pregnant women and women who are breastfeeding. In addition, it is prohibited for patients who are allergic to sildenafil citrate tablets. The drug is also prohibited to be used in combination with nitrates and other drugs. You should consult your doctor before using the drug and use the drug under the doctor’s guidance to avoid blind use of the drug.