Side Effects
and Safety of
Glucosamine
Most studies
involving humans
have found that
short-term use
of glucosamine
is
well-tolerated.
Side effects may
include
drowsiness,
headache,
insomnia, and
mild and
temporary
digestive
complaints such
as abdominal
pain, poor
appetite,
nausea,
heartburn,
constipation,
diarrhea, and
vomiting. In
rare human
cases, the
combination of
glucosamine and
chondroitin has
been linked with
temporarily
elevated blood
pressure and
heart rate and
palpitations.
Since
glucosamine
supplements may
be made from
shellfish,
people with
allergies to
shellfish should
avoid
glucosamine
unless it has
been confirmed
that it is from
a non-shellfish
source. The
source of
glucosamine is
not required to
be printed on
the label, so it
may require a
phone call to
the
manufacturer.
There is some
evidence
suggesting that
glucosamine, in
doses used to
treat
osteoarthritis,
may worsen blood
sugar, insulin,
and/or
hemoglobin A1c
(a test that
measures how
well blood sugar
has been
controlled
during the
previous three
months) levels
in people with
diabetes or
insulin
resistance.
Theoretically,
glucosamine may
increase the
risk of
bleeding. People
with bleeding
disorders, those
taking
anti-clotting or
anti-platelet
medication, such
as warfarin,
clopidogrel, and
Ticlid, or
people taking
supplements that
may increase the
risk of
bleeding, such
as garlic,
ginkgo, vitamin
E, or red
clover, should
not take
glucosamine
unless under the
supervision of a
healthcare
provider.
The safety of
glucosamine in
pregnant or
nursing women
isn't known.