Ein Heilmittel für die Behandlung der gutartigen Prostatahyperplasie Unterdrückt die Aktivität der 5α-Reduktase-Isoenzyme 1 und 2, die für die Umwandlung von Testosteron in 5α-Dihydrotestosteron verantwortlich sind. Dihydrotestosteron ist das wichtigste Androgen, das für die Hyperplasie des Drüsengewebes der Prostata verantwortlich ist.
Die maximale Wirkung von Dutasteride (Avodart) auf die Abnahme der Konzentration von Dihydrotestosteron ist dosisabhängig und wird nach 1-2 Wochen beobachtet. Nach Beginn der Behandlung. Nach 1 und 2 Wochen. Dutasterid in einer Dosis von 0,5 mg / Tag wird die durchschnittliche Konzentration von Dihydrotestosteron im Serum um 85% und 90% reduziert.
INTERACTIONS: Since dutasteride is metabolized by the CYP 3A4 isoenzyme, plasma dutasteride concentration may increase in the presence of CYP 3A4 inhibitors, and the clearance of dutasteride decreases with simultaneous application of CYP 3A4 inhibitors with verapamil (37%) and diltiazem (44%). At the same time, the clearance of dutasteride does not decrease with the use of another antagonist of calcium channels with amlodipine. The decrease in clearance and the corresponding increase in the effect of dutasteride in the presence of inhibitors of CYP 3A4 is not of great clinical significance due to the wide spectrum of drug safety. In vitro isoenzymes CYP 1A2, CYP 2C9, CYP2 C19 and CYP 2D6 do not participate in the metabolism of dutasteride in humans, dutasteride does not inhibit the enzymes of the cytochrome P450 system in humans participating in the metabolism of drugs. In vitro studies have established that dutasteride does not displace warfarin, diazepam, or phenytoin from binding to plasma proteins, nor do these components replace dutasteride. The interaction of dutasteride with tamsulosin, terazocine, warfarin, digoxin and colestyramine was studied. Clinically significant interaction was not detected. Although no specific studies on the interaction with other drugs have been conducted, about 90% of all patients in clinical studies of dutasteride received other concomitant therapy. No clinically significant adverse reactions were observed with simultaneous use of dutasteride with antihyperlipidemic drugs, ACE inhibitors, β-adrenoreceptor blockers, calcium channel blockers, GCS, diuretics, NSAIDs, phosphodiesterase type V inhibitors and quinolone antibiotics. According to a study to study the interaction of tamsulosin or terazocine in combination with Avodart for 2 weeks, no signs of pharmacokinetic or pharmacodynamic interaction were detected.
OVERDOSE: According to clinical studies, in volunteers, a single dose of dutasteride up to 40 mg / day (80 times higher than therapeutic) for 7 days did not cause undesirable manifestations, taking into account the safety of their use. In clinical studies, a dose of dutasteride was administered at 5 mg / day for 6 months without the appearance of additional adverse reactions compared with dutasteride at a dose of 0.5 mg / day. There is no specific antidote, therefore, in case of a possible overdose, symptomatic therapy is performed.