In what cases Viagra can refuse to work?

Despite the high effectiveness of Viagra there are a certain number of patients in which this drug does not improve erections. In many cases this is due to incorrect dosing. Patients, especially in early stages of treatment, should be encouraged to take Viagra on an empty stomach at least in 30 minutes before sexual activity. It is also important to explain patients that the drug starts its action only against the background of adequate sexual stimulation, and largely depends on it.

In many cases, treatment should begin with 100mg, which will provide a maximum response at the beginning of treatment and patients will inspire confidence in the success of treatment. In addition, studies have shown that in most patients the maximal effect of sildenafil is achieved after 6-8 reception, due to which many of the final assessments of the effectiveness of the drug should be made after several attempts of its application.

Currently, there are debates about long-term effectiveness of Viagra and opportunities of tachyphylaxis development. El-Galley with other researchers has conducted a telephone survey of 82 patients 2 years after the intake of Viagra. Forty-one (59%) respondents continued to take Viagra, while 37% were forced to increase the initial dose due to lower efficiency. Seventeen percent discontinued to treat with the drug due to lower efficiency. Long-term efficacy of Viagra was also investigated by Montorsi, who has tested 2618 patients taking the drug for 3 years. Overall, 96% were satisfied with treatment and only 1.6% stopped it due to low efficiency. Laboratory studies have also failed to confirm the existence of tachyphylaxis effect with Viagra. Thus, existing data do not confirm the presence of tachyphylaxis during long-term intake of Viagra.

In recent years, has been increased an interest in the possibility of Viagra using in various other diseases, such as varicocele.

In a study of Sairam has been evaluated the effect of Viagra on the severity of urination disorders in men with ED. After 1 and 3 months after treatment has been shown significant reduction in the severity of lower urinary tract symptoms, which was accompanied by improvement in erectile function.

Sildenafil leads to improvement in patients with primary and secondary pulmonary hypertension, as mentioned above. Another of the possible directions for future research is the use of Viagra in the treatment of endothelial dysfunction.

Thus, sildenafil has become the first effective oral treatment for erectile dysfunction, whose appearance has started the new era in the development of Sexual Medicine, which in recent years has become an independent branch of modern urology. Clinical efficacy of Viagra therapy has been evaluated in a large number of studies conducted in many countries around the world.