Sexual dysfunction : the roles of yohimbine hydrochloride and intracavernosal vasoactive drugs in the treatment of erectile dysfunction, the effect of transurethral resection of prostate on sexual functions and the impact of dihydrotestosterone on andropausal symptoms

The aim of this study was to clarify the effects of yohimbine hydrochloride and three intracavernosa l vasoactive agents in patients with erectile dysfunction and the effect of dihydrotestos terone gel in men with andropausal symptoms. The effect of transurethral resecti on of prostate (TURP) on sexual functions was also examined. Altogether 406 patients were included in five studies, and all patients were examined and controlled in the Oulu University Hospital during the years 1991-1998. Twenty-nine patients with mixed-type erectile dysfunction (ED) were recruited into a randomized, controlled, double-blind crossover comparison of placebo and high-dose yohimbine hydrochloride (36 mg per day orally). Positive clinical response s were obtained in 44% of the patients during yohimbine treatment and in 48% during placebo treatment. Thirty patient s with ED underwent an intracavernosa l injection test (ICI) using three different active agents (prostaglandin E1(PGE1) , papaverine hydrochloride (PV), moxisylyte (MS)) and physiological saline. PGE1 produced significantly better rigidity than either PV or MS. Sixty-nine patients with ED who had started ICI therapy with PGE1 at least three years previously were invited to acontrol exami nation to find out the long-term outcomeof this treatment and to evaluate thepatients’ overal satisfacti on with their sexual life.46.4% of thepatient shad discontinued PGE1 therapy, the mean time of using PGE1 having been 23.3 months (range 0-48 months) . 34.8% of the patientsreported that their own spontaneous erectionshad improved during thePGE1 therapy. The sexual functions of 155 patient s with benign prostati c hyperplasia (BPH) were evaluated before TURP and 6 and 12 months afterwards with questionnaires . Only 26% of the patient s had completel y satisfactory erections before TURP, while 22% had satisfactory erections 6 months later and 24% 12 months later. The majority of patients (about 70%) were satisfied with their sexual life both before and after theprocedure. 123 men with symptoms of andropause participated in a randomized, placebo-controlled study to assess the effects of dihydrotestosterone(DHT) gel in men with andropausal symptoms. Thedrug was administered transdermally once aday during six months. Early morning erections improved significantly (p<0.003) in the DHT group by the three-mont h control, the ability to maintain erections was better, and there was also a positive effect on libido. In the patient s with a elevated (>12) international index of the prostati c symptoms score (I-PSS) before DHT treatment , I-PSS decreased from 17.7 to 12.3 points. As a conclusion yohimbine hydrochloride is no better than placebo in the treatment of patients with mixed-type ED. PGE1, PV and MS are well tolerated, and PGE1 was shown to be the most effective drug of the three. ICI therapy with PGE1 in long-term use is safe and effective. Sexual functions in men did not change after TURP, and this group of aging men were fairly satisfied with their sexual lif e despite of the fact that they had some ED and one third of the patients had not had intercourse during the previous year. Transdermal administration of DHT in aging men improves sexual function.