There are only three oral drugs approved by the FDA to treat erection dysfunction: Cialis, Levitra, and Viagra. All work by increasing the flow of blood into the penis so that when a man is sexual" stimulated, he can get an erection.What Are the Differences Between Cialis, Levitra, and Viagra? Cialis, Levitra, and Viagra work by a similar mechanism to cause Erection. There are subtle differences in how long the drug works and how quickly it works. Levitra works a little longer than Viagra. They both take effect in about 30 minutes. With Levitra, the effects last for about 5 hours. With Viagra, the effects last approximately 4 hours.Cialis works a bit faster (within about 15 minutes), and the effects last much longer -- up to 36 hours in some cases.If One of These Drugs Isn't Effective for Erectile Dysfunction, Can I Try Another? Yes, but because these drugs work the same way, it's unlikely that you'll have success with one if you've failed to achieve an adequate erection with another.What Precautions Should I Take Before Taking One of These Drugs?There are certain situations in which these drugs may not be safe to take. Before taking them, tell your doctor:"    If you are allergic to any drugs, including Viagra or other ED medications. "    About any prescription or nonprescription medications you are currently taking, including herbal and dietary supplements. "    If you are scheduled for surgery, including dental surgery. "    If you take nitroglycerin or a long-acting nitrate to treat chest pain. The combination of Cialis, Levitra or Viagra with these drugs can cause dangerously low blood pressure. "    If you take alpha-blockers for blood pressure or prostate problems. The combination of Cialis or Levitra with these drugs can also cause dangerously low blood pressure. In addition, always follow the directions on your prescription label carefully and ask your doctor or pharmacist to explain any part that you do not understand. Take these drugs exactly as directed. Do not take more or less or take it more often than prescribed by your doctor. Do not take these drugs more than once a day.Who Should Not Take Cialis, Levitra or Viagra?If you have suffered from a heart attack, stroke or life threatening arrhythmia (irregular heart rate) within the last 6 months you should discuss other options with your doctor. It is also advised to avoid these drugs if you have uncontrolled high or low blood pressure or if you experience chest pain with sex.What Are the Side Effects of Cialis, Levitra and Viagra? Side effects are not common but they can occur. Side effects can include:"    Headache "    Upset stomach or ' heartburn' "    Flushing (feeling warm) "    Nasal congestion "    Changes in vision (color, glare) "    Back pain (with Cialis) Call your doctor if you experience severe forms of these symptoms or if they do not go away after 4-8 hours.

In response, Congress enacted the National Childhood Vaccine Injury Act of 1986, which pre-empted most vaccine lawsuits through an administrative compensation program, but the FDA-mandated safety investments were kept intact. The vaccine experience is a powerful illustration of how the duplication of safety through both the FDA and product liability harms patient access.Policy-makers and the public need to be confident that the FDA has in place the right set of tools to ensure that medicines are reasonably safe and that innovative new therapies for diseases like cancer and Alzheimer's reach patients as rapidly as possible. Both goals can be met through a sustained commitment to improving the FDA's ability to use the latest scientific discoveries in its rulemaking process. Earlier this year, the Supreme Court ruled in favor of pre-emption for medical devices. If the court interprets the law in favor of pre-emption for cheap celebrex as well, it will be a victory for patient access across the world.Tomas J. Philipson, a former senior economic adviser to the FDA commissioner, is chairman of Project FDA at the Manhattan Institute for Policy Research. 

Prudish pandas turn to ViagraChinese pandas are being given the anti-impotence drug Viagra, according to the Wen Hui Daily newspaper in Shanghai. It is hoped that the drug will boost their famously feeble attempts to mate. Poaching and loss of habitat have reduced the worldwide giant panda population to just 1,000 and many warnings of extinction have been made. Most efforts to breed the animals in captivity have failed, leading to a recent project to clone panda embryos with the intention of artificially implanting them. Coy boys The problem with many captive pandas is that they are curiously coy about amorous advances from the opposite sex. Whether Viagra, which helps stimulate an erection, will help is not known, but the newspaper said: "The male panda can only mate for at most 30 seconds at a time and hence the chances of getting the female pregnant are very low. "With Viagra, the male could last for up to 20 minutes." Mating myth Sally Nicholson, Head of International Policy at the World Wildlife Fund for Nature, told BBC News Online: "There is a myth about pandas being reluctant to mate. In the wild, they can certainly do it, but in captivity they do have a problem which no-one has yet cracked. "I say good luck to the researchers testing the Viagra, as long as they are very careful to avoid any damaging side effects." But Ms Nicholson, who is in frequent contact with WWF's panda programme in China, added that WWF's primary concern was the protection of the panda's habitat: "Pandas can survive in the next century if their habitats are protected - the recent logging ban by the Chinese government is very good news." After all, she pointed out, even if captive breeding was successful, "pandas cannot be reintroduced to habitat which is not there". Chinese medicine Zhang Hemin, director of a panda centre in the central province of Sichuan, told the the Wen Hui Daily he was unsure if Viagra would help. "We tried to give them Chinese medicine in the mid-1990s," he said. "As a result, the sex drive of the pandas did improve but they also became hot-tempered and attacked the females. That obviously wasn't so good and we had to end the experiment." Mr Zhang said: "The real problem is that many pandas do not know how to mate."

Dysfunction problems Useful for Impotence Following Prostate SurgeryMen with prostate cancer who have their prostate removed are usually free of cancer, but the procedure often comes with a cost -- impotence. A new study, however, shows that Viagra (sildenafil), the popular medication for erectile dysfunction, can restore impotency lost in surgery. Whether men respond, however, depends on how much nerve damage occurred during surgery.Each year some 200,000 men are diagnosed with prostate cancer and, of those, 50,000 will have to undergo surgical removal of the prostate."Incontinence and impotence are the two most common prostatectomy side effects. A large number of patients, even with nerve-sparing techniques, end up with erectile dysfunction," Milton Lakin, MD, who leads the medical urology section at Cleveland Clinic Foundation. "The first thing [doctors] want to do is a very good cancer operation. Cancers are being discovered early enough that in many cases it is possible to spare both nerves, or at least one."The new study, which appears in the November Journal of Urology, was completed by physicians at Baylor College of Medicine in Houston. It involved about 80 men who ranged in age from 47 to 76 years old. All were prescribed Viagra following prostate removal surgery. Based on their responses to a series of questionnaires, 53% had improved erections and 40% had improved ability to have intercourse.Among those with nerves spared on both sides of the prostate, almost 60% had improved erections and about 45% reported improvement in their ability to have intercourse. Of men who had nerves spared on one side of the prostate, close to 40% had improvement of their ability to have intercourse. For men with no nerves spared, the reported increase in erections dropped to 20%, with only 10% noting an improvement in the ability to have intercourse.At least one side effect each was experienced by 63% of the men, most commonly flushing, headache, nasal congestion, and heartburn.Brian Miles, MD, one of the study authors, called the results "gratifying" and noted that the findings indicate patients should start on the medication about six months after surgery.These findings confirm previous study results and put a greater spotlight on the prostate surgery itself, says Lakin, who was not involved in this study but has been part of nearly identical studies that produced similar results. "I am not a surgeon. I deal primarily with sexual dysfunction. But where I think this [study] will have the most impact is in causing physicians to pay more attention to nerve sparing," he says.Lakin says that he commonly prescribes Viagra following surgery for prostate cancer because other options are more invasive. "Unfortunately, it's very hard not to offer a patient a pill even if their nerves have been cut, but I am very honest with them. And if they call and say it didn't work, we go on from there."If Viagra fails, physicians can recommend other options, including injections and vacuum devices, both of which have good success rates, even among men whose nerves were damaged, according to Lakin