Treatment of men with erectile dysfunction, which consist in the inability to obtain or maintain an erection of the penis sufficient to undergo a satisfactory sexual intercourse.
Composition:
1 tabl powl. contains 100 mg of Sildenafil in the form of citrate.
Action:
Sildenafil is a potent selective inhibitor of cGMP-specific phosphodiesterase type 5 (PDE5), which is responsible for the distribution of cGMP in the corpus cavernosum. It triggers an erection through its peripheral action. It does not exhibit a direct relaxant effect on isolated human corpora cavernosa, but significantly increases the diastolic effect of nitric oxide on this tissue. During sexual arousal, when the metabolic reactions in which nitric oxide and cGMP are involved, inhibition of PDE5 activity by sildenafil causes an increase in cGMP concentration in the corpus cavernosum. Sexual arousal is essential for sildenafil to have the intended beneficial pharmacological effect. Sildenafil causes a slight and transient decrease in blood pressure, in most cases without significant clinical significance. It absorbs quickly. After oral administration on an empty stomach, Cmax in the serum occur after 30-120 minutes. The use of sildenafil during a meal reduces its absorption rate. Sildenafil and its major circulating N-desmethyl metabolite bind to plasma proteins approximately 96%. The degree of binding to proteins does not depend on the total concentrations of the drug. Sildenafil is primarily metabolised by the cytochrome P450 microsomal enzyme system, including its CYP3A4 isoenzyme and, to a lesser extent, CYP2C9. The main metabolite of sildenafil arises as a result of its N-demethylation. T0,5 is 3-5 hours. After oral administration, it is excreted as metabolites, mainly in the faeces and to a lesser extent in the urine.
Contraindications:
Hypersensitivity to sildenafil or other components of the preparation. Co-administration with nitric oxide eluting drugs (ie amyl nitrate) or nitrates. Severe liver dysfunction. Hypotension (<90/50 mmHg). Recently stroke or myocardial infarction. Established hereditary degenerative retinal disorders, i.e. dye retinopathy. Do not use in men whose sexual activity is not recommended (patients with severe cardiovascular disease such as unstable angina or severe heart failure) and men who have lost their sight in one eye due to non-arteritic anterior ischemic optic neuropathy regardless of whether this was related to previous exposure to a PDE5 inhibitor.
Precautions:
Do not use the product in women or people under 18 years of age. Before prescribing the preparation, the patient should be assessed for susceptibility to vasodilating, particularly during sexual activity (increased sensitivity is demonstrated by patients with left ventricular blood defect, eg aortic stenosis or hypertrophic cardiomyopathy, and a rare multiple organ system atrophy characterized by severe impairment of blood pressure control) arterial blood by the autonomic nervous system). Use with caution in patients with anatomical penile deformities (ie curvature, cavernous fibrosis or Peyronie's disease) and with conditions predisposing to priapism (eg sickle cell disease, multiple myeloma or leukemia). The safety and efficacy of concomitant use of sildenafil with other medicines used to treat erectile dysfunction have not been studied; combination therapy is not recommended. The preparation should be discontinued in case of sudden visual disturbances. The combination of sildenafil and ritonavir is not recommended. Caution should be exercised when administering sildenafil to patients who are taking alpha-blocker medications due to the risk of hypotension, which usually occurs within 4 hours of sildenafil administration. Sildenafil should only be used after careful consideration of possible benefits and risks in patients with bleeding disorders or active peptic ulcer disease.
Orally. Adults: 50 mg, depending on the needs, about 1 hour before planned sexual activity. Depending on the efficacy and tolerability of the drug, the dose can be increased to 75-100 mg or reduced to a dose of 25 mg. The maximum recommended dose is 100 mg. It is not recommended to take the drug more than once a day. If the medicine is taken with a meal, the onset of action may be delayed compared to taking the medicine on an empty stomach. In patients with mild or moderate renal impairment (creatinine clearance 30-80 ml / min) and in elderly patients, no dose adjustment is necessary. In patients with severe renal impairment (creatinine clearance <30 ml / min) or with liver intolerance, a 25 mg dose should be considered, and depending on the efficacy and tolerability of the drug, the dose may be increased to 50 mg, 75 mg or 100 mg. In patients co-administering CYP3A4 inhibitors (with the exception of ritonavir) or alpha-blockers, therapy with 25 mg is recommended.
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