Udenafil

When ATH:
G04BE

Pharmacological action.

Udenafil - is a selective reversible inhibitor of cyclic guanosine monophosphate (cGMP) - Specific phosphodiesterase type 5 (PDE5). Udenafil has no direct relaxing effect on the isolated corpus cavernosum, but when sexual stimulation enhances the relaxing effect of nitric oxide by inhibiting PDE-5, responsible for the breakdown of cGMP in the cavernous body. The result is relaxation of smooth muscles of arteries and blood flow to the tissues of the penis, that causes erections. The drug has no effect in the absence of sexual stimulation.

Pharmacokinetics

Absorption
After prima rapidly absorbed into Udenafil. Time of maximum plasma concentration (t max) is 30-90 minutes (average - 60 minutes). Half life (t ?) is 12 hours, udenafil high binding to plasma proteins (93,9%) prolongs its effectiveness to 24 hours after administration of only one dose. Receiving high-calorie food has no effect on absorption udenafil.

Metabolism:
Udenafil mainly metabolized with isoenzyme (СYP)3A4 цитохрома Р450.

Deduction:
In healthy people, the total clearance of udenafil 755 ml / min. Once inside Udenafil excreted as metabolites in the feces. Udenafil does not accumulate in the body. When taken daily to healthy volunteers in a dose udenafil 100 and 200 mg daily for 10 days, there were no significant changes in its pharmacokinetics.

Indications

Treatment of erectile dysfunction, characterized by the inability to achieve or retain an erection of the penis, sufficient for satisfactory sexual intercourse.

Dosing and Administration

The drug is taken orally, regardless of the meal.
The recommended dose is 100 mg, take over 30 minutes before anticipated sexual activity.
The dose may be increased to 200 mg, taking into account the individual efficacy and tolerability. The maximum recommended multiplicity of application - once a day.

Side effect

Cardio-vascular system – flushing.

CNS – dizziness, stiff neck, paresthesia.

On the part of the organ of vision – redness of the eyes blurred vision, sore eyes, increased lacrimation.

Dermatological reactions swelling of the eyelids, swelling of the face, hives.

From the digestive system – dyspepsia, abdominal discomfort nausea, toothache, constipation, gastritis.

On the part of the endocrine system – thirst.

The respiratory system – nasal congestion, shortness of breath, dry nose.

On the part of the musculoskeletal system – parasynovitis.

From the body as a whole – headache, chest discomfort, sensation of heat chest pain, stomach ache, fatigue.

During postmarketing surveillance in applying udenafil were also described other adverse events: palpitation, nose bleed, noise in ears, diarrhea, allergic reactions (skin rash, эritema), prolonged erection, feeling of general discomfort, sensation of cold or heat, postural dizziness, cough.

Contraindications

Hypersensitivity to any component of the drug;
Simultaneous reception of nitrates and other "donators" nitric oxide.

Pregnancy and lactation

Not intended for use in women.

Paediatric use

Not intended for use in children and adolescents under the age of 18 years.

Overdose

In single dose of the drug at a dose of 400 mg of adverse events were comparable to those observed in the employment udenafil at lower doses, but they were more frequent.
Treatment: symptomatic. The dialysis does not accelerate the elimination of udenafil.

Drug Interactions

Inhibitors of cytochrome P450 isoenzymes CYP3A4 (ketoconazole, itraconazole, ritonavir, indinavir, cimetidine, Erythromycin, grapefruit juice) may enhance the action of udenafil.

Ketoconazole (dose 400 mg) increases bioavailability and C max udenafil (dose 100 mg) almost twice (212%) and in 0,8 times (85%), respectively. Ritonavir and indinavir znachitelyno usilivayut action udenafil.

Dexamethasone, rifampin and anticonvulsants (Carbamazepine, phenytoin and phenobarbital) may accelerate the metabolism udenafil, therefore, co-administration of the above drugs reduces the effect of udenafil.

Co-administration of udenafil (30 mg / kg, orally) and nitroglycerine (2,5 mg / kg intravenously once) It did not show any effect on the pharmacokinetics of udenafil in experimental studies, However, the simultaneous use of nitroglycerin and udenafil not recommended due to the possible decrease in blood pressure. Udenafil and drugs from the group of alpha-blockers are vasodilators, Therefore, when co-administered should be appointed in minimal doses.