Sildenafil citrate tablets are a kind of drug that prolongs the erection time of men’s penis, which usually lasts for about two hours after ingestion into the body. This kind of drug can make the capillaries dilate after ingestion, so that the cavernous body of the penis can be filled with more blood, and the penis can be erected quickly after external stimulation or mental stimulation, so that the effect of the drug can be fully exerted. This kind of drug can prolong the time of sexual intercourse for men after ingestion, generally lasting about two hours, but the effect of the drug may vary in duration depending on the individual’s physique. For patients with underlying diseases such as cardiovascular disease, this drug is prohibited. In addition, patients are advised not to use this drug for a long time because it is mainly metabolized by the liver and excessive intake may increase the burden on the liver. Therefore, patients need to take it under the guidance of a doctor to avoid adverse effects, which may endanger people’s health.