N-acetyl glucosamine is a chemical that comes from the outer shells of shellfish.
Don't confuse N-acetyl glucosamine with other forms of glucosamine, such as glucosamine hydrochloride or glucosamine sulfate. They may not have the same effects.
Read glucosamine product labels carefully for their content. Most glucosamine products contain glucosamine sulfate or glucosamine hydrochloride. Although glucosamine sulfate and glucosamine hydrochloride are marketed together in combination products with N-acetyl glucosamine, there haven't been any human studies that have evaluated these combinations for treating osteoarthritis.
You may also see chitosan as an ingredient in some glucosamine products. Chitosan is a form of N-acetyl glucosamine that has been chemically altered.
N-acetyl glucosamine is taken for osteoarthritis and inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease.
How it works
N-acetyl glucosamine might help protect the lining of the stomach and intestines.
Not ProvenInflammatory bowel diseases, including ulcerative colitis and Crohn's disease
There is some early evidence that N-acetyl glucosamine taken by mouth or rectally might decrease symptoms of IBD in children with Crohn's disease or ulcerative colitis.
There isn't enough information available to know if N-acetyl glucosamine is safe.There has been some concern that glucosamine products might cause allergic reactions in people who are sensitive to shellfish. Glucosamine is produced from the shells of shrimp, lobster, and crabs. But allergic reactions in people with shellfish allergy are caused by the meat of shellfish, not the shell. There are no reports of allergic reactions to glucosamine in people who are allergic to shellfish. On the positive side, there is also some information that people with shellfish allergy can safely take glucosamine products.There has also been a concern that glucosamine might increase the amount of insulin in the body. Too much insulin might lead to high blood pressure and high levels of cholesterol and other blood fats called triglycerides. While animal research seems to confirm that glucosamine can increase cholesterol, researchers haven't found this effect in people. In fact, research findings to date show that glucosamine does not seem to increase blood pressure or raise cholesterol levels in people over age 45 who take glucosamine sulfate for up to 3 years.
Pregnancy and breast-feeding: Not enough is known about the use of N-acetyl glucosamine duringpregnancyandbreast-feeding. Stay on the safe side and avoid use.
Asthma: Researchers aren't sure why, but glucosamine might make asthma worse in some people. If you have asthma, use caution when trying glucosamine.
Diabetes: Some early research suggested that glucosamine might raise blood sugar in people with diabetes. However, more reliable research indicates that glucosamine does not seem to significantly affect blood sugar control in people with type 2 diabetes. As long as you routinely monitor your blood sugar, you can probably take glucosamine safely.
Surgery: N-acetyl glucosamine might affect blood sugar levels and might interfere with blood sugar control during and after surgery. Stop taking N-acetyl glucosamine at least 2 weeks before a scheduled surgery.
Warfarin (Coumadin) is used to slow blood clotting. There are several reports showing that taking glucosamine with or without chondroitin increase the effect of warfarin (Coumadin) on blood clotting. This can cause bruising and bleeding that can be serious. Don't take glucosamine if you are taking warfarin (Coumadin).
ModerateMedications for cancer (Chemotherapy)
There is some concern that N-acetyl glucosamine might decrease the effectiveness of some medications for cancer. But it is too soon to know if this interaction occurs.
MinorAcetaminophen (Tylenol, others)
There has been concern that glucosamine might increase blood sugar in people with diabetes. There was also the concern that glucosamine might decrease how well medications used for diabetes work. However, research now indicates that glucosamine probably does not increase blood sugar in people with diabetes. Therefore, glucosamine probably does not interfere with diabetes medications. To be cautious, if you take N-acetyl glucosamine and have diabetes, monitor your blood sugar closely.Some medications used for diabetes include glimepiride (Amaryl), glyburide (Diabeta, Glynase PresTab, Micronase), insulin, pioglitazone (Actos), rosiglitazone (Avandia), chlorpropamide (Diabinese), glipizide (Glucotrol), tolbutamide (Orinase), and others.There is some concern that taking glucosamine and acetaminophen (Tylenol, others) together might affect how well each works. But more information is needed to know if this interaction is a big concern.