Stop taking VIAGRA and call your healthcare provider right away if you have any sudden vision loss sudden hearing decrease or hearing loss. By investigating these possibilities, people can get the prescription drugs they need to treat their ED issues without having to pay a high price. Sildenafil treats erectile dysfunction by increasing blood flow to the penis during sexual stimulation. To use the oral liquid: Shake the bottle well for at least 10 seconds before each use. Quantity: Know how much free Viagra you can get and whether you must meet any restrictions or requirements before receiving the samples. However, it is important to understand that alcohol might impair erection and penis sensitivity. · 2. Rex MD – Free Viagra Samples. Rex MD is a men’s health-focused telemedicine service. They provide free prescription pharmaceutical samples for erectile dysfunction and hair loss and. Sildenafil (Viagra) is used to treat erectile dysfunction (impotence; inability to get or keep an erection) in men. Sildenafil (Liqrev, Revatio) is used to improve the ability to exercise in adults (Liqrev, Revatio) and children 1 year of age and older (Revatio) with pulmonary arterial hypertension (PAH; high blood pressure in the vessels.  · These all improve blood supply to the penis. In combination with sexual stimulation, the drugs can produce an erection sufficient to initiate and complete intercourse. There is also a fast-dissolving form of Levitra, called Staxyn, that you put under your tongue. One ED drug, Cialis, is FDA-approved for .