in chronic prostatitis/chronic pelvic pain syndrome (cp/cpps) there is pelvic pain of unknown cause, lasting longer than 6 months, as the key symptom. symptoms may wax and wane. pain can range from mild discomfort to debilitating. pain may radiate to back and rectum, making sitting difficult. dysuria, arthralgia, myalgia, unexplained fatigue, abdominal pain, constant burning pain in the penis, and frequency may all be present. frequent urination and increased urgency may suggest interstitial cystitis (inflammation centred in bladder rather than prostate). ejaculation may be painful, as the prostate contracts during emission of semen, although nerve- and muscle-mediated post-ejaculatory pain is more common, and a classic sign of cp/cpps. some patients report low libido, sexual dysfunction and erectile difficulties. pain after ejaculation is a very specific complaint that distinguishes cp/cpps from men with bph or normal men.