Drug title

Zudena (Udenafil)

Pharmacological action

Medication for the treatment of erectile dysfunction, reversible selective inhibitor of cGMP-specific FDE5.

Udenafil has no direct relaxant effect on the isolated cavernous body, but with sexual stimulation, it enhances the relaxant effect of nitric oxide by inhibiting FDEF5, which is responsible for the breakdown of cGMP in the cavernous body. A consequence of this is relaxation of arterial smooth muscles and blood flow to penile tissues, which causes an erection. The drug has no effect in the absence of sexual stimulation.

In vitro studies have shown that Zudena (Udenafil) is a selective inhibitor of FDE5 enzyme. FDE5 is present in the smooth muscles of the corpora cavernosa, in the smooth muscles of vessels of internal organs, in skeletal muscles, platelets, kidneys, lungs, and cerebellum. Udenafil is 10,000 times more potent as an inhibitor against FDE5 than against FDE1, FDE2, FDE3, and FDE4, which are localized in the heart, brain, blood vessels, liver, and other organs.

In addition, Zudena (Udenafil) is 700 times more active with respect to FDE5 than with respect to FDE6, found in the retina and responsible for color vision. Zudena (Udenafil) does not inhibit FDE11, which explains the absence of myalgia, lower back pain and manifestations of testicular toxicity.

Zudena (Udenafil) improves erection and the possibility of successful intercourse. The action of the drug has an optimal duration of up to 24 hours. The effect occurs within 30 minutes after taking the drug in the presence of sexual arousal.

Zudena (Udenafil) in healthy individuals causes no significant changes in systolic and diastolic blood pressure compared to placebo when lying and standing (the average maximum decreases are 1.6/0.8 mm Hg and 0.2/4.6 mm Hg, respectively).

Zudena (Udenafil) does not cause changes in color recognition (blue/green), which is due to its low affinity for FDE6. Udenafil does not affect visual acuity, electroretinogram, intraocular pressure and pupil size.

When studying Zudena (Udenafil) in men, no clinically significant effect of the drug on the number and concentration of sperm, motility and morphology of sperm cells was found.

Pharmacokinetics

After oral administration, udenafil is quickly absorbed. Tmax is 30-90 min (on average - 60 min). High-fat food intake has no effect on absorption of udenafil.

The high plasma protein binding of udenafil (93.9%) prolongs the period of its effectiveness up to 24 hours after a single dose. Udenafil does not accumulate in the body. When healthy volunteers take udenafil in doses of 100 mg and 200 mg daily for 10 days, no significant changes in its pharmacokinetics were found.

Udenafil is mainly metabolized with participation of CYP3A4 isoenzyme. T1/2 is 12 hours. In healthy volunteers total clearance of udenafil is 755 ml/min. After oral administration, udenafil is excreted as metabolites in the feces.

Contraindications for use

Simultaneous use of nitrates and other nitric oxide donors; hypersensitivity to udenafil.

Cautions

Caution should be exercised when using udenafil in patients with uncontrolled arterial hypertension (BP >170/100 mm Hg), arterial hypotension (BP < 90/50 mm Hg); patients with hereditary degenerative retinal diseases (including retinitis pigmentosa and proliferative diabetic retinopathy). ); patients with hereditary retinal degenerative diseases (including retinitis pigmentosa, proliferative diabetic retinopathy); patients who have had a stroke, myocardial infarction or coronary artery bypass surgery within the last 6 months; patients with severe hepatic or renal insufficiency; in the presence of congenital syndrome of prolonged QT interval or prolongation of the QT interval due to taking drugs; in patients with a predisposition to priapism, as well as in patients with anatomical deformity of the penis, in the presence of a penile implant.

The potential risk of complications during sexual activity in patients with such cardiovascular diseases as unstable angina or angina pectoris occurring during sexual intercourse; chronic heart failure II-IV functional class (according to NYHA classification) developed during the last 6 months; uncontrolled heart rhythm disorders should be taken into account.

Simultaneous use of udenafil and calcium channel blockers, alpha-adrenoblockers or other hypotensive agents may cause an additional decrease in systolic and diastolic BP by 7-8 mm Hg.

Sexual activity has a potential risk for patients with cardiovascular diseases, so treatment of erectile dysfunction, including the use of udenafil, should not be performed in men with heart disease, in which sexual activity is not recommended.

Patients with left ventricular outflow tract obstruction (aortic stenosis) may be more sensitive to the action of vasodilators, including FDE inhibitors. Despite the absence of cases of prolonged erection (more than 4 hours) and priapism (painful erection lasting more than 6 hours) during clinical trials, such phenomena are characteristic of this class of drugs. If an erection lasts more than 4 hours (regardless of the presence of pain), patients should immediately seek medical advice. If there is no timely treatment, priapism may lead to irreversible damage of erectile tissue and erectile function.

Due to the lack of clinical data on the use of udenafil in patients older than 71 years, the use in these patients is not recommended.

The use of udenafil in combination with other treatments for erectile dysfunction is not recommended.

Effect on the ability to drive vehicles and mechanisms

In patients whose activity is connected with driving vehicles and operating mechanisms, the individual reaction to admission of udenafil should be determined.

Indications for the active substance UDENAFIL

Treatment of erectile dysfunction characterized by the inability to attain or maintain a penile erection sufficient for satisfactory intercourse.

Dosing regimen

It is taken orally. The recommended dose is 100 mg. If necessary, taking into account individual efficacy and tolerability, the dose can be increased to 200 mg. Maximum recommended frequency of use is 1 time per day.