Duloxetin: Wirkmechanismus am unteren Harntrakt und auf den Onuf-Nukleus

Zusammenfassung

Harninkontinenz ist das Unvermögen, die Blasenentleerung willentlich zu kontrollieren. Belastungsinkontinenz ist die häufigste Art der Inkontinenz bei Frauen. Zurzeit stehen keine akzeptierten oder zugelassenen Medikamente zur Behandlung der Belastungsinkontinenz zur Verfügung. Eine Vielzahl von Studien sehen eine Verbindung zwischen den Neurotransmittern Serotonin und Noradrenalin in der Kontrolle des unteren Harntrakts. Auf der Basis dieser Eigenschaften gibt es mit Duloxetin, einem kombinierten Serotonin-/Noradrenalinwiederaufnahmehemmer, einen neuen therapeutischen Ansatz. Duloxetin scheint am präsynaptischen Neuron im Onuf-Nukleus zu wirken. Die Wirkungsweise von Duloxetin wurde in tierexperimentellen Studien untersucht. In einer doppelblinden, randomisierten, plazebokontrollierten Studie bei Frauen mit Belastungsinkontinenz zeigte sich eine signifikante und klinisch relevante Senkung der Harninkontinenzepisoden unter Duloxetin. Als häufigste Nebenwirkung trat Übelkeit auf. Diese Ergebnisse deuten darauf hin, dass der Einsatz von Duloxetin in der Behandlung der Belastungsinkontinenz viel versprechend ist und die Lebensqualität der Frauen verbessern kann.

Abstract

Urinary incontinence is the inability to willingly control bladder voiding. Stress urinary incontinence (SUI) is the most frequently occurring type of incontinence in women. No specific and approved medication is yet available to treat stress urinary incontinence. Numerous studies have implicated the neurotransmitters, serotonin and noradrenaline in the central neural control of the lower urinary tract function. On the basis of these characteristics, duloxetine, a combined serotonin/norepinephrine reuptake inhibitor, may be a good therapeutic alternative. Duloxetine appears to act on the presynaptic neuron of the Onuf nucleus. The effectiveness of duloxetine was studied in animal experiments. In a double-blind, randomized placebo-controlled clinical trial in women with stress urinary incontinence there was a significant reduction in urinary incontinence episodes under duloxetine treatment. The most frequent adverse effect observed was nausea. In summary, these results indicate that duloxetine may prove to be an effective treatment for stress urinary incontinence in women and help improve their quality of life.

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