Glucosamine sulfate is a naturally occurring chemical found in the human body. It is in the fluid around joints. Glucosamine also exists in other places in nature. For example, glucosamine sulfate used in dietary supplements is often obtained from the shells of shellfish. Glucosamine sulfate used in dietary supplements does not always come from natural sources. It can also be made in a laboratory.

There are different forms of glucosamine including glucosamine sulfate, glucosamine hydrochloride, and N-acetyl glucosamine. These different chemicals have some similarities, but they may not have the same effects when taken as a dietary supplement. Most of the scientific research on glucosamine has involved glucosamine sulfate.

Dietary supplements that contain glucosamine often contain additional ingredients. These additional ingredients are frequently chondroitin sulfate, methylsulfonylmethane (MSM), or shark cartilage. Some people think these combinations work better than taking just glucosamine sulfate alone. So far, researchers have found no proof that combining the additional ingredients with glucosamine adds any benefit.

Applications

Glucosamine sulfate is most commonly used for osteoarthritis. It is also used for many other conditions, but there is no good scientific evidence to support these uses.

Osteoarthritis. Most research shows that taking glucosamine sulfate can provide some pain relief for people with osteoarthritis, especially those with osteoarthritis of the knees. For some people, glucosamine sulfate might work as well as over-the-counter and prescription pain medications such as acetaminophen or ibuprofen; however, pain medications work quickly while glucosamine sulfate can take 4-8 weeks before it provides pain relief. Also, people who take glucosamine sulfate often still need to take pain medications for pain flare-ups.

In addition to relieving pain, glucosamine sulfate might also slow the breakdown of joints and prevent the condition from getting worse if it is taken for several years. Some research shows that people who take glucosamine sulfate might be less likely to need total knee replacement surgery.

Correlational research

There are several kinds of glucosamine products. The most research showing benefit is for products that contain glucosamine sulfate. Products that contain glucosamine hydrochloride do not seem to work as well. Many products contain both glucosamine with chondroitin, but there is no evidence that these products work any better than glucosamine sulfate by itself.

Some research shows that taking a specific product containing glucosamine sulfate, methylsufonlylmethane, white willow bark extract, ginger root concentrate, Indian frankincense extract, turmeric root extract, cayenne, and hyaluronic acid (Instaflex Joint Support, Direct Digital, Charlotte, NC) in three divided doses daily for 8 weeks reduces joint pain in people with knee pain. But this product doesn't seem to help joint stiffness or function. Other early research shows that taking 1500 mg of glucosamine sulfate daily for 28 days does not reduce knee pain in athletes following a knee injury. However, it does seem to improve knee movement.

Multiple sclerosis (MS). Early research shows that taking 1000 mg of glucosamine sulfate by mouth daily for 6 months might reduce the relapse of multiple sclerosis.