The recommended dose of sildenafil is 50mg, and the best results are produced by taking it about 1 hour before the start of sexual intercourse. Sildenafil can increase blood flow to the corpus cavernosum of the male penis in the presence of sexual stimulation, improving erectile function in men, and is mainly used clinically to treat erectile dysfunction. This product is recommended to be taken as needed, with a recommended dose of 50mg, which can be increased to 100mg or decreased to 25mg depending on individual results, up to once a day. It is best taken about 1 hour before sexual intercourse. Common adverse reactions to sildenafil include abnormal vision, nasal congestion, back pain, myalgia, headache, flushing, dizziness, and rash, and it is contraindicated in people with known hypersensitivity to the product. It is recommended to consult a physician before taking the medication and should not be taken blindly on your own.