physician before taking any new medicines. According
to the NIH, throat swelling may occur if glucosamine
reacts negatively in people with shellfish allergies.
Glucosamine taken above the recommended dos-
ages could decrease the effectiveness of insulin or other
such drugs that control blood sugar levels in diabetes.
According to the NIH, some studies show a connec-
tion while other studies do not; however, the connec-
tion has been suggested as possible by the medical
community.
Reports from the NIH suggest that glucosamine
may also increase the risk of bleeding especially when
taking aspirin, blood thinners, anti-platelet drugs, and
non-steroidal anti-inflammatory drugs. The use of
glucosamine has also been possibly linked to the
increase in the frequency and severity of asthma.
Since glucosamine is not approved by the FDA, its
safety and formulation is determined solely by the
manufacturer. Thus, quality and content may vary
among manufacturers. Tests have been performed by
ConsumerLab.com, a leading provider of independent
tests for nutritional and health products and services.
Technicians at the laboratory report that the majority
of companies manufacturing glucosamine for con-
sumer use provide at least 90% of the amount of glu-
cosamine stated on the label.
The Arthritis Foundation recommends that, if
using glucosamine, consumers should buy from estab-
lished companies (because they can more easily be held
accountable for their products); read the product label
carefully (if need be, ask the pharmacist questions);
consult with the family doctor before trying new med-
icines; verify the source of the medical problem before
beginning glucosamine; make sure the physician is
aware of any future plans to take glucosamine; and
do not reduce or eliminate prescription medicines one
is already taking.
If deciding to take glucosamine, try it between six
to eight weeks. It generally takes this amount of time
before any noticeable effects are felt. Sometimes, no
effects are felt. If a reduction of symptoms is not noticed
at the end of this period of time, the Arthritis Founda-
tion states that glucosamine will probably not help.
Complications
The use of alcohol, tranquilizers, sedatives, anti-
seizure drugs, anti-anxiety drugs, muscle relaxants,
and antihistamine medicines may intensify the drowsi-
ness side effect that is possible with glucosamine.
Thus, if taking glucosamine and any of these drugs
together, users should be aware (and warned) that it
may adversely affect one’s concentration. Consumers
should talk with a medical professional before taking
glucosamine.
People who are overweight, have diabetes, or liver
disease should check their blood sugar levels more
frequently when taking glucosamine because it is an
amino sugar. If taking blood-thinning medication or
daily aspirin therapy, blood clotting time should be
tested more frequently.
A person can overdose on glucosamine. The
amount of glucosamine varies with the supplemental
form. Pure glucosamine hydrochloride is at a concen-
tration of about 83% in the glucosamine base; pure
glucosamine sulfate is approximately 65%, and pure
N-acetyl glucosamine is around 75%.Parental concerns
According to the NIH, there is no scientific evi-
dence to show that glucosamine should be given to
children. Methylsulfonylmethane (MSM), which is
sometimes packaged with glucosamine, has been
shown to have a relationship with autism, but whether
that association is good or bad is not currently known.
Osteoarthritis does affect children. Clinical stud-
ies have not proven whether or not glocosamine—
either in children or adults—should be recommended
as a medical therapy for osteoarthritis. Some studies
show that glucosamine can help people with mild to
moderate osteoarthritis and prevent the deterioration
of cartilage. However, other studies do not show these
benefits. The majority of studies have been performed
with glucosamine hydrochloride and glucosamine sul-
fate; but not with N-acetyl-glucosamine.
In any case, the effects of these glucosamine sup-
plements on a growing child or developing baby are
not yet known. For that reason, glucosamine is not
recommended for, and should not be taken by, chil-
dren. Because of the lack of long-term effects on a
developing fetus and child, women who are pregnant
and women who could become pregnant are advised
by the Arthritis Foundation not to take glucosamine.Resources
BOOKS
Bartlett, Susan J.Clinical Care in the Rheumatic Diseases.
Atlanta, GA: Association of Rheumatology Health
Professionals, 2006.
Imboden, John B, David B. Hellmann, and John H. Stone,
eds.Current Rheumatology Diagnosis and Treatment.
New York: Lange Medical Books/McGraw-Hill, 2004.
PERIODICALS
Bruyere, O, K. Pavelka, L.C. Rovati, et al. ‘‘Glucosamine
sulfate reduces osteoarthritis progression inGlucosamine