Viagra is the trade name and generic name for Sildenafil Citrate tablets. The price of Sildenafil Citrate ranges from $30 to $500. The price of Sildenafil Citrate tablets varies depending on whether it is domestic or imported and the specifications. Sildenafil citrate tablets are indicated for the treatment of erectile dysfunction in men. The price of this drug is affected by many factors such as manufacturer, sales channels, specifications, packaging, imported or domestic and so on, and is not fixed. Currently, its selling price for a box ranges from 30 yuan to 500 yuan. The specific price is subject to local pharmacies and medical institutions. Male patients can take sildenafil citrate tablets 0.5~4 hours before sexual activity. Adverse effects of the drug include dizziness and hypotension. Sildenafil citrate tablets are not indicated for use in women. Sildenafil is contraindicated in people who are allergic to Sildenafil Citrate Tablets, patients who are using nitroglycerin, sodium nitroprusside or other nitrate drugs. The drug should be applied under medical supervision.