Osteoarthritis is the most common arthritis in the world. It affects millions of people with age being the greatest risk factor for developing the disease. The burden of disease will worsen with the aging of the world's population. The disease causes pain and functional disability. The direct costs of osteoarthritis include hospital and physician visits, medications, and assistive services. The indirect costs include work absences and lost wages. Many studies have sought to find a therapy to relieve pain and reduce disability. Glucosamine hydrochloride (HCl) is one of these therapies. There are limited studies of glucosamine HCl in humans. Although some subjects do report statistically significant improvement in pain and function from products combining glucosamine HCl and other agents, glucosamine HCl by itself appears to offer little benefit to those suffering from osteoarthritis.