Sildenafil citrate tablets work mainly to help erections and are mainly used to treat erectile dysfunction. Sildenafil belongs to a kind of phosphodiesterase inhibitor type 5, after oral administration, through selective inhibition of PDE5, enhancement of the nitric oxide (NO)-cGMP pathway, elevation of cGMP levels and lead to the relaxation of penile corpus cavernosum smooth muscle, so as to enable erectile dysfunction patients to produce a natural erection response to sexual stimulation. However, sexual stimulation is required for it to be effective after taking it. Adverse reactions such as abnormal penile erection, headache, dyspepsia, abnormal vision, nausea, and rash may occur after administration. Because sildenafil can enhance the antihypertensive effect of nitrate drugs, leading to intractable hypotension, it is absolutely forbidden to use the two together, and the common nitroglycerin is a nitrate drug. In addition, this drug is also prohibited for women, people who are allergic to this product, children, and people whose recent cardiovascular status makes them unfit for sexual intercourse. Specific drugs, please use under the guidance of a specialist physician or pharmacist, do not take drugs blindly, so as not to affect health.