But in , Pfizer announced that it settled litigation against Teva Pharmaceuticals. As a result, Teva would be permitted to produce a generic version of Viagra in the United States on December 11, , or earlier depending on the circumstances. According to the FDA , generic medicines work the same way and provide identical benefits as brand-name drugs. In fact, generic drugs must meet rigorous standards to receive FDA approval.

The upside for patients is that generic meds are usually cheaper than brand-name ones. Another brand name of sildenafil, called Revatio, is used to treat pulmonary arterial hypertension high blood pressure in the lungs and improve exercise ability in men and women with this condition.

Viagra is in a class of medicines known as phosphodiesterase PDE inhibitors. It works by increasing blood flow to the penis. The U. Do not take sildenafil if you are also using a nitrate drug for chest pain or heart problems.

This includes nitroglycerin, isosorbide dinitrate, and isosorbide mononitrate. Nitrates are also found in some recreational drugs such as amyl nitrate or nitrite "poppers". Taking sildenafil with a nitrate medicine can cause a sudden and serious decrease in blood pressure. Sildenafil can decrease blood flow to the optic nerve of the eye, causing sudden vision loss. This has occurred in a small number of people taking sildenafil, most of whom also had heart disease, diabetes, high blood pressure, high cholesterol, or certain pre-existing eye problems, and in those who smoked or were over 50 years old.

It is not clear whether sildenafil is the actual cause of vision loss. Tell your doctor if you are pregnant. It is not known whether this medicine will harm an unborn baby. If other conditions and medications aren't the culprit, consider nondrug treatments. Though ED drugs are effective, our medical experts warn that they should be used cautiously because they can cause potentially serious side effects. The risks may include an increased chance of heart attack or stroke among men already at risk of such events—including those with coronary disease—as well as fertility problems and worsened sleep apnea.

In some men, the drugs may also cause temporary vision or hearing problems. You should not take ED drugs if you take a nitrate medicine, such as nitroglycerin pills, for heart problems. The combination can cause a dangerous drop in blood pressure. Editor's Note: These materials were made possible by a grant from the state Attorney General Consumer and Prescriber Education Grant Program, which is funded by a multistate settlement of consumer fraud claims regarding the marketing of the prescription drug Neurontin gabapentin.

I've spent nearly a decade reading, " squinching " at, and interpreting health research, and another couple of years looking at why medications cost so much. In my spare time, you'll find me giving unsolicited health advice to friends and family, practicing my asanas, biking, and juggling. Daily MedNews.

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