The first mention of erectile dysfunction (ED) is noted in the manuscripts of Ancient Egypt. Since then, there have been continuous attempts to improve the sexual potential of men, but a revolutionary breakthrough came with the discovery by Furchgott, Ignarro and Murad of the role of nitric oxide in the work of the cardiovascular system. The authors received the Nobel Prize and, in the course of further research, created sildenafil, which since 1998 has continued its triumphal march across the planet.
Sildenafil is known to many as a drug for the treatment of ED, but the spectrum of its therapeutic options is wider. The efficacy and safety of sildenafil was evaluated in 48 randomized, double-blind, plecebo-controlled, parallel-group trials involving 11,364 men with ED. It has been shown that in all age groups, including those over 75 years of age, the effectiveness of sildenafil citrate was high, and the frequency of side effects, among which headache and hot flashes predominated, was low.
Taking sildenafil citrate leads to an improvement in erectile function in patients of different ages, regardless of the etiology, severity and duration of ED. Sildenafil affects both arterial and venous blood flow in the penis, making it indicated in the first place for vasculogenic ED. The drug improves the cavernous electrical activity, which justifies its use in the neurogenic form of the disease.
Another recent study confirmed the generally good tolerability of phosphodiesterase type 5 inhibitors (PDE-5). The authors emphasize that there are no studies comparing different drugs in this group, all comparisons were made with placebo.
Confirmation of the efficacy and safety of sildenafil was obtained in a population study based on the example of residents of large cities in China. Studying the efficacy of various doses of sildenafil citrate in 3674 patients with ED, we concluded that the satisfaction of patients who took 100 mg of sildenafil was higher than that of those who took sildenafil citrate 50 mg. In general, it is recommended to approach the selection of the dose personally.
Exercise, diet, normalization of plasma glucose levels are insufficient to restore erectile function in patients with diabetes mellitus. A systematic review of 17 well-designed studies confirmed the efficacy and safety of sildenafil in diabetic patients with ED. Sildenafil citrate did not increase adverse reactions in diabetic patients taking metformin and thiazolidine. In the treatment of urological diseases associated with ED (hypogonadism, benign prostatic hyperplasia), potentiation of the effect of the combined use of basic therapy and sildenafil was noted. It is emphasized that the daily intake of sildenafil in patients with ED after prostatectomy gives a less pronounced effect than the intake “on demand”, which is absolutely logical, since PDE-5 only induces an erection with sexual stimulation. Fracture of the pelvic bones with damage to the urethra naturally leads to the development of ED. However, even in such a severe group, daily intake of sildenafil is effective in 61.5% of cases.
No drug in the PDE-5 group has a 100% effect in the treatment of ED. To find out the reasons for this phenomenon, a molecular genetic study was carried out in Spain, which showed genetic polymorphism in responses to PDE-5. As it turned out, the effectiveness of treatment with PDE-5 is genetically determined and cannot be changed. There was also a clear correlation between glycemic status and the effectiveness of treatment with sildenafil.
Recently, non-drug methods of treating patients with ED have become popular, in particular, extracorporeal shock wave therapy. An experimental study was carried out, which showed that this method while taking sildenafil significantly increases the effectiveness of treatment. Some patients prefer orally dissolving tablets that do not require swallowing and drinking with water, and there are already such tablets on the market.
Chronic prostatitis, both commonplace and specific, can be complicated by ED. Hypothetically, one can expect a positive effect of sildenafil citrate in prostatitis, since it has been shown that sildenafil affects the course of the inflammatory process, since it reduces the activity of pro-inflammatory factors. After taking sildenafil, TNF-α immediately decreases, the level of C-reactive protein decreases. However, along with the anti-inflammatory effect, sildenafil reduces the activity of ciprofloxacin in the treatment of patients with chronic prostatitis complicated by ED; this must be taken into account when prescribing therapy to such patients.
Those who are moderate in sexual issues claim that the problem of ED is exaggerated, that a person may well be happy, for example, doing his favorite job or hobby. However, our studies have shown that this is not the case: in the course of a multicenter cohort study, a positive correlation was found between the quality of male sexual function and the level of their overall success. In women, however, this dependence is not traced, in part, apparently, because the gender role of a woman does not depend on her sexual satisfaction.
We set out to study the assessment by sexual partners of men with ED of their sex life before their men started taking PDE-5 and after treatment.
Material and methods
An open-label monocenter cohort study was conducted with the participation of 128 men with mild to moderate ED, aged 32 to 54 years (mean 42.1 years). All patients had not previously received PDE-5. Patients were prescribed sildenafil 50 mg “on demand” 1 hour before the alleged intercourse. The second visit to the doctor was scheduled after 2 weeks. therapy for possible dose adjustment. The third, final visit was scheduled after 3 months. from taking the first dose of sildenafil. The effectiveness of treatment was assessed on the scale of the International Index of Erectile Function, patients recorded adverse reactions in their diaries. When a strong or prolonged (more than 6 hours) undesirable effect appeared, patients came to an unscheduled appointment with a doctor.
After 3 months, the wives (regular sexual partners) of men with effective treatment were asked about their husbands’ satisfaction with the quality of treatment. Wives were asked to independently assess the initial sex life of the couple and the changes that occurred after treatment using a questionnaire. The ultimate goal of the study was to analyze this estimate.
Of 128 men, only one (0.78%), while taking sildenafil, developed nasal congestion, impaired color perception and headache so badly that he stopped taking the drug. Another 15 (11.7%) had side effects, but the patients considered them insignificant and the therapy continued.
In 24 (18.75%) men with very good erections, but with adverse reactions, the dose was reduced to 25 mg, which did not affect the effectiveness, but improved tolerance. On the contrary, 32 (25.0%) patients, the attending physician considered it necessary to increase the dose to 100 mg, the remaining 72 (56.25%) continued therapy with the initial dose of sildenafil citrate 50 mg. Taking sildenafil and, accordingly, sexual intercourse (or an attempt to it) was performed on average with a frequency of 2.7 times a week.
The positive effect of sildenafil was noted by 83 (64.84%) patients. When asked to invite their wives for a conversation, the two admitted that they were living in a homosexual couple, 27 men did not have a permanent girlfriend and realized their restored sexual potency in casual relationships, 11 women refused to talk, and 43 agreed to answer questions.
Initially, 38 wives (88.37%) rated the couple’s sex life as unsatisfactory, although 5 women did not consider their husband’s ED as a problem, since they themselves had low sexual desire. After 3 months. On therapy with sildenafil, 19 (44.18%) women considered their family sex life good, 22 (51.16%) – excellent. At the same time, in the opinion of 2 (4.65%) women, there were no changes, which once again proves that for a woman in sex, one good erection from a sexual partner is not enough.
Thus, 41 (95.35%) women were satisfied with the result of their husband’s treatment with sildenafil citrate and felt that improving the quality of erection had a positive effect on family life.
Medicinal correction of sexual deviations in women remains questionable, probably, the leading role is played by the psychological component of the process. Our study showed that 95.35% of women are satisfied with the results of treatment of their sexual partners with sildenafil, therefore, sildenafil affects the sexual function of women, albeit indirectly.
There are a number of pitfalls in using IFDE-5. First, there are many fakes and substandard generics on the market. Spectral analysis of basic sildenafil and sildenafil citrate was performed. Sildenafil crystallizes as basic sildenafil, sildenafil citrate with a higher crystal characteristic. The presence of various impurities violates the quality characteristics of sildenafil citrate.
When treating with sildenafil, the general rules for taking medications are observed. Medicines are recommended to be taken with water and not with any other drink in order to avoid interaction and prevent drug inactivation or biotransformation during competitive metabolism with the participation of cytochrome isoenzymes CYP3A4 and CYP2C9. Inhibitors of isoenzymes CYP3A4 and CYP2C9 (ketoconazole, erythromycin, cimitidine) decrease metabolism and increase the concentration of sildenafil in the blood. In this case, treatment with sildenafil begins with a dose of 25 mg, since otherwise, due to competitive metabolism, an overdose of sildenafil citrate is possible, which has a hepatotoxic effect. Plasma levels of sildenafil were compared in men who swallowed tablets with water diluted with lemon or orange juice. They found that orange juice significantly increased the concentration of sildenafil in the blood (the peak concentration was 44% higher, the “cleansing period” was 30% longer). Lemon juice, to the surprise of the researchers, had no effect on the pharmacokinetics of sildenafil.
Sildenafil plays an important, albeit indirect, role in a woman’s life – it increases her sexual satisfaction by improving the erection of her sexual partner. According to the study, 95.35% of women are satisfied with the results of treatment of their sexual partners with sildenafil.