Active ingredient Estriol is an oestrogen (a female hormone.) Urinary incontinence is a reasonably common ill effect of neutering bitches. The cause of the incontinence is bladder sphincter mechanism incompetence. Fortunately for us this is usually readily treatable by replacing the female hormone in low doses - and Incurin is that low dose tablet we use. There is no set dose rate – we just find out the dose by trial. Once daily dosing is often needed, sometimes every other day, sometimes two tablets daily. There are few side effects but sometimes the tablet may cause feminising – i.e. enlargement of the vulva and attraction to male dogs. Withdrawing the drug reverses this.