The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.
Adults (18 years and older)
In most available studies, 500 milligrams of glucosamine sulfate has been taken by mouth as tablets or capsules three times daily for 30 to 90 days. Once daily dosing as 1.5 grams (1,500 milligrams) has also been used. Limited research has used 1,500 milligrams daily as a crystalline powder for oral solution or 500 milligrams of glucosamine hydrochloride three times daily. Dosing of 20 milligrams per kilogram of body weight daily has also been recommended in some publications. One study used a dose of 2,000 milligrams per day for 12 weeks.
Another kind of glucosamine that has been used is a topical form in combination with chondroitin for a four-week period. Safety and effectiveness of these formulations are not clearly proven.
Glucosamine hydrochloride provides more glucosamine than glucosamine sulfate, although this difference likely does not matter when products are prepared to provide a total of 500 milligrams of glucosamine per tablet.
Children (younger than 18 years)
There is not enough scientific evidence to recommend the use of glucosamine in children.
Research in children has shown that there could be a relationship between the ingestion of MSM (methylsulfonylmethane) and autism; whether it is beneficial or harmful is unclear. MSM is often marketed with glucosamine as a dietary supplement and at this time should be avoided in children.