Toward better treatment for lower urinary tract symptoms associated with benign prostatic hyperplasia?

The most effective and fastest acting pharmacotherapeutic relievers of lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH) are the selective α1A-adrenoceptor antagonists such as tamsulosin, silodosin, and alfuzosin (7). This class of drugs relieves symptoms primarily by inhibiting the binding of norepinephrine to α1A-adrenoceptors located on the smooth muscle cells of the urethra and prostate. This antagonism of α1A-adrenoceptors relaxes the urethral and prostatic smooth muscle allowing urine to flow more easily through the urethral obstruction caused by prostate enlargement. Despite this, the α1-adrenoceptor antagonist class of drugs is only useful in treating mild to moderate symptoms associated with BPH. More severe symptoms require surgical intervention to widen the urethral passage sufficiently to allow smoother flow of urine (8). Another important limitation of α1A-adrenoceptor antagonists is their efficacy, as improvement of urinary symptom scores and flow will generally not exceed 50%.