Proof-of-concept Study to Evaluate the Safety and Efficacy of Tryptophan in Patients with BPH.

Benign prostatic hyperplasia (BPH) is one of the most prevalent human diseases and a major cause of lower urinary tract symptoms (LUTS). Some men respond to current medical treatment (mainly α-1 adrenoreceptor antagonists and 5 α-reductase inhibitors), but a large proportion of patients continues to need a surgical procedure to treat resistant LUTS or even more serious complications of BPH, creating the emerging necessity for novel pharmacological therapies. Oxitriptan may have a possible positive effect on BPH associated symptoms with probably no impact in sexual function (which is a common side effect of the current drugs for BPH associated symptoms). Also, improvement in symptoms could be higher than that of current drugs used for this condition. This is a single-center parallel group, randomized clinical trial. The study will take place in Hospital de Braga (Urology department). Eligible patients will be randomized to receive tamsulosin 0.4mg (once a day, q.d.) or 5-HTP (5-hidroxitriptophan) 100mg (three times a day, t.i.d.), for 6 months.