Viagra is the trade name, generic name of sildenafil citrate tablets, the efficacy of which is to treat male erectile dysfunction, while Priligy refers to sildenafil dapoxetine mixed tablets, the efficacy of which is to treat male erectile dysfunction combined with premature ejaculation. 1. Sildenafil Citrate Tablets: It is a type 5 phosphodiesterase inhibitor, which can prolong the duration of erection by enhancing the effect of nitric oxide in the process of penile erection, thus exerting a therapeutic effect on erectile dysfunction in men over 18 years old. However, it should be noted that sildenafil citrate tablets are contraindicated in people who are allergic to it or are using nitrate drugs such as isosorbide mononitrate, and there may be adverse reactions such as headache and visual abnormalities in the process of using the drug. 2. Sildenafil Dapoxetine Mixed Tablets: It contains 2 kinds of active ingredients: sildenafil and dapoxetine. Sildenafil and Dapoxetine are two kinds of active ingredients. Sildenafil is the same as above; Dapoxetine is a 5-hydroxytryptamine reuptake inhibitor, which can regulate the ejaculatory reflex by inhibiting the reuptake of 5-hydroxytryptamine by the neurons, so as to treat the premature ejaculation of men aged 18-64 years old. Sildenafil Dapoxetine Mixed Tablets, in addition to the above contraindications and adverse reactions, is also prohibited in people who are allergic to the ingredients of Dapoxetine, the presence of active heart disease or moderate to severe liver injury, adverse reactions include dizziness, nausea and so on. Sildenafil Citrate Tablets or Sildenafil Dapoxetine Mixed Tablets users, must be under the guidance of a doctor to regulate the use of medication, do not blindly take medication or increase or decrease the dosage of their own, so as not to cause adverse consequences.