Terazosine administration for treatment of vesico-urethral reflex dyssynergia in dogs with respect to efficacy and side effects

Abstract

Vesico-urethral reflex dyssynergia (VURD) is a disorder in which there is a miscommunication between the musculus detrusor of the bladder wall and the urethral sphincter. An impaired micturition is caused by insufficient relaxation of the urethral sphincter when the musculus detrusor contracts. 3, 8

Previously, prazosin (Minipress®) was used for the treatment of VURD. Since prazosin is no longer available in the Netherlands, terazosin (Terazosine® or Hytrin®) is used for the medical treatment of VURD. Terazosin has been chosen based on previous studies. Availability, efficiency and types of administration (e.g. tablets vs capsules) were taken into account. Terazosin is a registered human drug. Like prazosin, terazosin is an α1-receptor antagonist and is used for the temporarily treatment of functional signs of benign prostate hyperplasia (BPH) in humans awaiting prostatic surgery. It selectively blocks the postsynaptic α1-adrenoceptors which leads to an improved urine flow.4, 9, 14 Research was conducted in healthy male dogs to determine the effect of terazosin. The results of this study exposed a markedly reduced sphincter tonus in healthy dogs treated with terazosin. 11 In this study an attempt is made to demonstrate the therapeutic effect of terazosin in dogs suffering from VURD, as well as to describe revealed side effects.

Little is know about the use of terazosin to treat dogs suffering from VURD. The purpose of this study is to describe terazosin administration for treatment of VURD in dogs with respect to efficacy, safety and side effects. The results of this study will also be compared with the results of a previous study (prazosine administration, Utrecht University, Faculty of Veterinary Medicine, 2008).