- More than half of men in their sixties and 90 percent in their seventies have some symptoms of BPH.
- In the United States, 375,000 hospital stays each year involve a diagnosis of BPH.
As a man ages, it is common for the prostate gland to become enlarged. This condition is called benign prostatic hyperplasia (BPH). Although BPH rarely causes symptoms before the age of 40, an increasing percentage of men will become symptomatic as they get older. Symptoms of BPH stem from obstruction of the urethra and gradual loss of bladder function, which results in incomplete emptying of the bladder. Common complaints of BPH include urinary urgency and frequency, and multiple instances of nocturnal urination.
Treatment of BPH
Four drugs are approved by the FDA to treat BPH. One drug, finasteride (Proscar®), inhibits production of a hormone which is involved with prostate enlargement. Although widely used in the United States, finasteride (Proscar®) is not covered in New Zealand or Ontario, Canada. (Ontario Ministry of Health and Long Term Care 2001; PHARMAC 2002)
Three newer drugs, alpha-1 blockers (alpha-1 adrenoceptor antagonists), act to relax the smooth muscle of the prostate and bladder neck to improve urine flow and to reduce bladder outlet obstruction. Using an alpha-1 blocker along with finasteride is more effective than either drug alone to relieve the symptoms and prevent BPH progression. (NIH, NIDDK 2002) The two-drug regimen reduced the risk of BPH progression by 67 percent, compared to 39 percent for an alpha blocker alone or 34 percent for finasteride alone.
Drugs in the pipeline for BPH
- Studies to evaluate phytotherapeutic agents to treat BPH are under way. (NIH 2002, Andersson 2002) [NIDDK and the National Center for Complementary and Alternative Medicine (NCCAM) currently fund a small, single-center pilot project using saw palmetto for BPH, and plan to fund a large, multi-center clinical trial using Serenoa repens (saw palmetto) and Pygeum africanum in men with BPH, beginning on about September 30, 2002.]
- Endothelin and muscarinic receptor antagonists are being evaluated for the treatment of BPH. (Andersson 2002)
- Subtypes of alpha-1 blockers are being investigated. (Andersson 2002)
There are several drugs currently in clinical trials for treatment of BPH. (PhRMA 2002) New approaches for the treatment of BPH and resulting urinary tract symptoms are being investigated. (Andersson 2002) These new approaches target sites both within and exterior to the prostate gland. By their effect on the smooth muscle in the bladder wall, muscarinic receptor antagonists may reduce the urinary urgency and frequency associated with BPH. Endothelin receptor antagonists may prevent cell proliferation in both the prostate gland and the bladder. Moreover, these agents may also affect muscle contraction in the bladder wall, decreasing some of the symptoms of BPH. In addition, drugs directed at specific subtypes of alpha-1 adrenoceptors may prove more effective and tolerable than nonselective compounds.