Check our more Tadalafil for sale: 1) Tadalafil 20/40 (10 pills) Sunrise – 12$ Sildenafil is used for: Treating high blood pressure in the lungs (pulmonary arterial hypertension [PAH]). It may also be used for other conditions as determined by your doctor. Sildenafil is a phosphodiesterase type 5 (PDE5) inhibitor. It works by relaxing and dilating the blood vessels in the lungs. This lowers the blood pressure in the lungs and helps to improve your ability to exercise. Sildenafil is used to treat high blood pressure in the lungs (pulmonary hypertension). It works by relaxing and widening the blood vessels in your lungs which allows the blood to flow more easily. Decreasing high blood pressure in the lungs allows your heart and lungs to work better and improves your ability to exercise. This medication is not recommended for use in children. Discuss the risks and benefits of this medication with the doctor. OTHER USES: This section contains uses of this drug that are not listed in the approved professional labeling for the drug but that may be prescribed by your health care professional. Use this drug for a condition that is listed in this section only if it has been so prescribed by your health care professional. Sildenafil citrate , sold as Viagra, Revatio and under various other trade names, is a drug used to treat erectile dysfunction and pulmonary arterial hypertension (PAH). It was originally discovered by Pfizer scientists Andrew Bell, David Brown, and Nicholas Terrett. It acts by inhibiting cGMP-specific phosphodiesterase type 5 (PDE5), an enzyme that promotes degradation of cGMP, which regulates blood flow in the penis. Since becoming available in 1998, sildenafil has been the prime treatment for erectile dysfunction; its primary competitors on the market are tadalafil (Cialis) and vardenafil (Levitra). Viagra is a brand-name of erectile dysfunction medication Sildenafil Citrate. This drug belongs to the class of PDE-5 inhibitors and is used to deal with erectile dysfunction, or male impotence. This medication works when a man is sexually excited, but it doesn�t cause sexual arousal itself. So, this medication can provide its effect when a man is sexually aroused. In order to understand how Sildenafil works, we should discuss the mechanism of getting an erection. When a man is sexually stimulated and aroused, a certain substance is released in the erectile tissue which is called nitric oxide. This substance stimulates an enzyme that releases another substance known as cyclic guanosine monophosphate, which in its turn relaxes the cells of smooth muscle. This causes the arteries in the penis to widen and as the result, the blood flows into the penis more easily. One more effect of the medication is that it cases the erectile tissue itself to fill with blood. As a result, erection arouses. If a man is not sexually aroused, the brain will not provoke the release of nitric oxide and the body will not produce cyclic guanosine monophosphate. Sildenafil Citrate is used by a great number of men suffering from erectile dysfunction as it has shown that it works safe and effectively and provide a good result in dealing with impotence.