Those who don’t feel comfortable discussing ED with an in-person provider or lack time to visit a doctor’s office may find online ED prescriptions beneficial. If you are taking any of these medications, speak with your doctor or pharmacist. All PDE5 inhibitors, including Viagra and Cialis, require a valid prescription regardless of the pharmacy or provider. Take sildenafil as needed before sexual activity. Alcohol: Consumption of alcohol in large amounts may decrease the ability to get an erection and may also temporarily decrease blood pressure, causing dizziness and fainting. Sildenafil treats erectile dysfunction by increasing blood flow to the penis during sexual stimulation. Stop taking VIAGRA and call your healthcare provider right away if you have any sudden vision loss sudden hearing decrease or hearing loss.CIALIS VIAGRA. Toll Free Phone: Toll Free Fax: 24 hours / 7 days a week. See what customers have to say about our products and .  · Descriptions. Sildenafil is used to treat men who have erectile dysfunction (also called sexual impotence). Sildenafil belongs to a group of medicines called phosphodiesterase 5 (PDE5) inhibitors. These medicines prevent an enzyme called phosphodiesterase type-5 from working too quickly. The penis is one of the areas where . Still, if your doctor says it’s okay for you to use and you end up paying out-of-pocket, you can still get the generic for a lot less than Viagra. According to price-comparison site test1.ru