Clinical Efficiency of Viagra: How Were the Clinical Trials Conducted?

According to numerous clinical trials and researches involving volunteers with different degree of erectile dysfunction, Sildenafil citrate has a rather high effectiveness. Large-scale trials have been conducted since late 1990-es when Viagra was discovered and covered over three thousand men from different countries of the world. Pfizer, probably, is a record-breaker among pharmaceutical companies in terms of time and efforts spent on the new drug testing.

Results of Clinical Trials

The effectiveness of Viagra was estimated in more than 3000 men aged from 19 to 87. The time duration of erectile disorders in these men was from 6 months to 26 years (5 years in average). Etiology of erectile dysfunction was organic, psychogenic and mixed. Results of these trials show that Viagra is effective for the treatment of erectile dysfunction and improving indicators of successful sexual acts in a large number of patients including those suffering from diabetes, spinal cord injuries, and other concomitant clinical states as well as in patients taking other medicaments.

Viagra acts in response to a natural sexual stimulation for erectile function restoration. All in all, from 70 to 90 percent of test persons taking Viagra and from 10 to 30 men taking placebo reported on the improving of erection. Dosages of Viagra 50 and 100 milligrams are well tolerated and are highly effective for the treatment of erectile dysfunction. Results of observation 550 patients who had received treatment for at least a year showed that effectiveness of Viagra remained unchanged for a long time.

What does Efficiency of Viagra Depend on?

Though Viagra is considered a very effective drug, its efficiency to a large extent depends on the type of erectile dysfunction as well as on concomitant diseases. For example, the drug is rather effective for the treatment of vascular erectile dysfunction. However, for the treatment of patients with pathologic venous drainage, its efficiency is much lower.

Unfortunately, there is no (and cannot be) a drug, which could treat all the diseases, or, in this case, all types of erectile dysfunction with a similar level of efficiency. Viagra is also not a panacea, though it can really help to a great number of men. Viagra is effective for the ED treatment in men with atherosclerosis, injury of nerves of the blood vessels in the penis, diabetes. However, as it has been said, its efficiency is lower for the treatment of ED in men with venous drainage.

There are some medical states when taking of Viagra is absolutely contraindicated. The essential contraindication for taking these drug is simultaneous taking of nitrates of nitrate-containing drugs. Usually, these are drugs for the treatment of heart and cardiovascular problems. For example, this group includes an innocuous glycine. The fact is that Sildenafil citrate and nitrates are taken together to cause a sudden fall in blood pressure, which in some cases can cause a serious damage to health. Take this fact into account before buying Viagra.