Urinary incontinence, defined as a loss of bladder control, may result from many biological factors, including weak bladder muscles and inflammation, as well as from nerve damage associated with diseases such as multiple sclerosis (MS) and Parkinson’s disease. It is believed that more than one in ten Americans over age 65 suffer from incontinence, particularly women.
Several recent clinical trials in the past have indicated that cannabinoid therapy could reduce incidents of incontinence. Investigators at Oxford’s Centre for Enablement in Britain, writing in the February 2003 issue of the journal Clinical Rehabilitation, reported that bladder control was improved by self-administered doses of whole-plant cannabinoid extracts when compared to placebo in patients suffering from MS and spinal cord injury.
These initial findings were followed by investigators at London’s Institute for Neurology in an open-label pilot study of cannabis-based extracts for bladder dysfunction in 15 patients with advanced multiple sclerosis. Investigators determined “urinary urgency, the number of and volume of incontinence episodes, frequency, and nocturia all decreased significantly” following cannabinoid therapy. “Cannabis-based medicinal extracts are a safe and effective treatment for urinary and other problems in patients with advanced MS.”
A multi-center, randomized placebo-controlled trial involving 630 patients administered oral doses of cannabis extracts or THC confirmed these findings in 2006. It was reported by researchers that subjects administered cannabis extracts experienced a 38 percent reduction in incontinence episodes from baseline to the end of treatment, while patients administered THC experienced a 33 percent reduction, suggesting a “clinical effect of cannabis on incontinence episodes.
“In light of these findings, experts have recommended the use of cannabinoids as potential ‘second-line’ agents to treat incontinence.
 Wade et al. 2003. A preliminary controlled study to determine whether whole-plant cannabis extracts can improve intractable neurogenic symptoms. Clinical Rehabilitation 17: 21-29.
 Brady et al. 2004. An open label pilot study of cannabis-based extracts for bladder dysfunction in advanced multiple sclerosis. Multiple Sclerosis 10: 425-433.
 Freeman et al. 2006. The effect of cannabis on urge incontinence in patients with multiple sclerosis: a multicentre, randomized placebo-controlled trial. The International Urogynecology Journal 17: 636-641.
 University of Pittsburgh Medical Center Press Release. May 21, 2006. ” Marijuana-derived drug suppresses bladder pain in animal models.”
 Kalsi and Fowler. 2005. Therapy insight: bladder dysfunction associated with multiple sclerosis. Nature Clinical Practice Neurology 2: 492-501.