Botox for BPH?

What are the pros and cons of treating BPH (an enlarged prostate) with Botox injections?

Kevin R. Loughlin, M.D., M.B.A., director of Urologic Research at Brigham and Women’s Hospital, answers:

Doctors typically prescribe medication for the treatment of BPH, using two classes of drugs. Alpha-1 blockers deal with the “going” problem by relaxing certain muscles in the prostate and urinary tract. In contrast, the 5-alpha-reductase inhibitors deal with the “growing” problem by reducing the size of the prostate. But the drugs don’t offer immediate relief: the 5-alpha-reductase inhibitors in particular can take weeks to work. They can also cause side effects, such as low blood pressure and erectile dysfunction.

Surgery and minimally invasive treatments for BPH using heat or lasers can cut away or destroy prostate tissue. These procedures create an enlarged passageway for urine. But surgery comes with risks, including erectile dysfunction, ejaculatory problems, infections, and, rarely, urinary incontinence.

Some preliminary evidence indicates that injections of Botox (botulinum toxin type A) might be an effective alternative. Why? In laboratory studies, it appears to induce apoptosis, or programmed cell death, preventing the overgrowth of prostate cells. It also seems to slow some prostate activity, shrinking the prostate and relaxing muscles in the prostate gland and bladder that can restrict the flow of urine.

One relatively recent study of Botox included 41 men whose symptoms of BPH persisted despite taking medication. None of the men experienced significant side effects after a Botox injection, and symptoms and quality of life improved by more than 30% in three-fourths of the participants. The improvements lasted for a year.

Sounds promising, but there’s still a lot we don’t know about using Botox for the treatment of BPH. For example, we don’t have long-term data about its effectiveness or its impact on sexual function. Nor have we determined the best way to inject it, the best injection sites, or the best dose. And no clinical trials have compared Botox with a placebo or other therapy.

Until we know more, I recommend sticking with established therapies. If they don’t relieve your symptoms, you could try the injections, but only as part of a clinical trial.

SOURCE: Chuang YC, Chiang PH, Yoshimura N, et al. Sustained Beneficial Effects of Intraprostatic Botulinum Toxin Type A on Lower Urinary Tract Symptoms and Quality of Life in Men with Benign Prostatic Hyperplasia. BJU International 2006;98:1033–37. PMID: 16956361.

Originally published Jan. 1, 2009; Last reviewed April 18, 2011