benign prostatic hyperplasia
"I had been getting up more frequently, recently 5x/night.  I have other sleep issues, uncontrolled sleep apnea while on BiPAP, so waking more often left me sleepy.  I then had surgery for an inguinal hernia.  The anesthesia shut me down, I couldn't urinate and was catheterized.  The doc put me on tamsulosin with immediate results.  I generally get up once now.  No side effects."