Medikamentöse Therapie des benignen Prostatasyndroms (BPS)

Zusammenfassung

Zur medikamentösen Behandlung des benigen Prostatasyndroms werden α1-Rezeptorenblocker (Alfuzosin, Doxazosin, Tamsulosin und Terazosin), 5α-Reduktasehemmer (Dutasterid und Finasterid) und deren Kombination eingesetzt. Für den Einsatz von Pflanzenextrakten fehlt nach wie vor die Evidenz, der Einsatz von anticholinergen Substanzen alleine oder in Kombination mit anderen BPS-Medikamenten befindet sich zurzeit in Erprobung und sollte nicht außerhalb von klinischen Studien erfolgen. Bei allen Medikamenten ist der Plazebo-Effekt erheblich. Daher ist eine Abweichung von den empfohlenen Dosierungen schnell mit einem Wirkverlust über Plazebo hinaus verbunden. α1-Rezeptorenblocker zeigen einen schnellen Wirkeintritt und sind hinsichtlicht der Symptomenlinderung den 5α-Reduktasehemmern leicht überlegen. Alle α1-Rezeptorenblocker sind bei adäquater Dosierung ähnlich wirksam, quantitative Unterschiede zeigen sich aber im Nebenwirkungsprofil. 5α-Reduktasehemmer lindern ebenfalls BPS-assoziierte Symptome wobei die Symptomenlinderung volumenabhängig ist. Prostatavolumen-abhängige Komplikationen des BPS (OP-Risiko und Risiko eines akuten Harnverhaltes) können durch 5α-Reduktasehemmer gemindert werden. Medikamentenlangzeitstudien haben die Überlegenheit der Kombinationstherapie gegenüber der Monotherapie mit α1-Rezeptorenblockern und 5α-Reduktasehemmern bei Patienten mit einem hohen Progressionsrisiko bewiesen. Diese Überlegenheit ist begleitet von einer Kombination der Nebenwirkungsprofile und deren absoluten Zunahme. Neben der schlechteren Verträglichkeit führt die Kombinationstherapie Steigerung der Therapiekosten. Um so wichtiger ist es frühzeitig zu entscheiden, wer medikamentös oder operativ behandelt werden sollte.

Abstract

α1-Receptor blockers (alfuzosin, doxazosin, tamsulosin and terazosin), 5α-reductase inhibitors (dutasteride and finasteride) and combinations thereof are used in the drug treatment of benign prostatic syndrome. As before, there is still no evidence supporting the use of plant extracts, the use of anticholinergic substances alone or in combination with other BPS drugs is currently under investigation and should not be attempted outside of clinical trials. For all drugs the placebo effect is considerable. Accordingly, deviations from the recommended doses are rapidly associated with an activity loss over that of placebo. α1-Receptor blockers show a rapid onset of action and are slightly superior to 5α-reductase inhibitors with regard to the relief of symptoms. All α1-receptor blockers are similarly effective at adequate doses, however, quantitative differences are seen in the side effect profiles. 5α-Reductase inhibitors also provide relief from BPS-associated symptoms with the relief being volume-dependent. Prostate volume-dependent complications of BPS (operation risk and risk of acute urine retention) can be reduced by 5α-reductase inhibitors. Long-term drug studies have demonstrated the superiority of combination therapies over monotherapies with α1-receptor blockers and 5α-reductase inhibitors in patients with a high risk for progression. This superiority is accompanied by a combination of the respective side-effect profiles and their absolute increase. Besides poorer tolerability, combination therapies also result in higher costs. Thus, it is important to decide at an early stage which patients are to be treated with drugs and which by surgery.

Schlüsselwörter

α1-Rezeptorenblocker - Alfuzosin - Doxazosin - Tamsulosin - Terazosin - 5α-Reduktasehemmer - Dutasterid - Finasterid - benignes Prostatasyndrom - medikamentöse Therapie

Key words

α1-Receptor blockers - alfuzosin - doxazosin - tamsulosin - terazosin - 5α-reductase inhibitors - dutasteride - finasteride - benign prostatic syndrome - drug therapy

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