Alpha-lipoic acid is an antioxidant that is manufactured in the human body.
Antioxidants are substances that work by attacking "free radicals," waste
products created when the body turns food into energy. There are also many
sources of free radicals in the environment such as ultraviolet rays, radiation,
and toxic chemicals in cigarette smoke, car exhaust, and pesticides. Free
radicals cause harmful chemical reactions that can damage cells in the body,
making it harder for the body to fight off infections. As a result a person
becomes more susceptible to long term diseases such as diabetes and liver
Alpha-lipoic acid works together with other antioxidants such as vitamins C
and E. It is important for growth, helps to prevent cell damage, and helps the
body rid itself of harmful substances.
Several studies suggest that treatment with ALA may help reduce pain,
burning, itching, tingling, and numbness in people who have nerve damage (called
peripheral neuropathy) caused by diabetes. Alpha-lipoic acid has been used for
years for this purpose in Europe. Other studies have shown that alpha-lipoic
acid speeds the removal of glucose (sugar) from the blood of people with
diabetes and that this antioxidant may prevent kidney damage associated with
diabetes in animals.
Alpha-lipoic acid may prove useful in the treatment of chronic hepatitis
because it relieves stress on the liver and helps rid the body of toxins. There
have been several case reports of use of alpha-lipoic acid in combination with
silymarin (milk thistle) and selenium (a substance with liver-protecting and
antioxidant properties) to help treat hepatitis C (a serious type of hepatitis
contracted from blood and bodily fluids that does not have an adequate cure or
It has also been used in conjunction with silymarin to treat Amanita
poisoning. Amanita is a highly poisonous mushroom that causes liver
Brain Function and Stroke
Because alpha-lipoic acid can pass easily into the brain, it has protective
effects on brain and nerve tissue and shows promise as a treatment for stroke
and other brain disorders involving free radical damage. Animals treated with
alpha-lipoic acid, for example, suffered less brain damage and had a four times
greater survival rate after a stroke than the animals who did not receive this
supplement. While animal studies are encouraging, more research is needed to
understand whether this benefit applies to people as well.
Additional conditions for which alpha-lipoic acid may prove useful include
heart failure, human immunodeficiency virus (HIV), cataracts, and glaucoma. More
research is underway in these areas.
Good food sources of alpha-lipoic acid include spinach, broccoli, beef, yeast
(particularly Brewer's yeast), and certain organ meats (such as the kidney and
Alpha-lipoic acid supplements are available in capsule form.
How to Take It
There are no known scientific reports on the pediatric use of alpha-lipoic
acid. Therefore, it is not currently recommended for children.
Alpha-lipoic acid can be purchased in dosages ranging 30 mg to 100 mg
tablets. Currently there are no established recommended doses for
supplementation. For general antioxidant support, the recommended dose of ALA is
20 mg to 50 mg per day.
Manufacturers of alpha-lipoic acid suggest one or two 50-mg capsules daily as
a dietary supplement.
Studies that have been successful in improving nerve function in diabetics
have used 600 mg of alpha-lipoic acid per day in divided doses.
Because of the potential for side effects and interactions with medications,
dietary supplements should be taken only under the supervision of a
knowledgeable healthcare provider. This is especially true for those who are
pregnant or breastfeeding.
Skin rash has been reported rarely from alpha-lipoic acid.
Finally, because alpha-lipoic acid has been associated with improved blood
sugar control, people with diabetes should follow their blood sugar levels
carefully when taking this supplement in order to avoid hypoglycemia (low blood
sugar). Your doctor may decide that a reduction in dosage of insulin or oral
blood sugar-lowering drugs is needed if you are taking this supplement.
If you are currently being treated with any of the following medications, you
should not use alpha-lipoic acid without first talking to your healthcare
Amikacin and Gentamicin
In an animal study, alpha-lipoic acid supplements reduced side effects,
particularly toxicity to the ear, associated with these antibiotics. Additional
studies are needed to confirm these effects in people.
Cisplatin and Cyclophosphamide
The use of alpha-lipoic acid supplements in animals protected against toxic
side effects associated with these medications.
Thyroid-regulating Medications, Levothyroxine
Rats given alpha-lipoic acid supplements had altered thyroid hormone
function, but improved cholesterol levels. Blood hormone levels and thyroid
function tests should be monitored closely in people taking thyroid hormones who
are also taking alpha-lipoic acid.
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Review Date: April 2002
Reviewed By: Participants in the review process include: Jacqueline A. Hart, MD,
Department of Internal Medicine, Newton-Wellesley Hospital, Harvard University
and Senior Medical Editor Integrative Medicine, Boston, MA; Gary Kracoff, RPh
(Pediatric Dosing section February 2001), Johnson Drugs, Natick, Ma; Steven
Ottariono, RPh (Pediatric Dosing section February 2001), Veteran's
Administrative Hospital, Londonderry, NH; Margie Ullmann-Weil, MS, RD,
specializing in combination of complementary and traditional nutritional
therapy, Boston, MA. All interaction sections have also been reviewed by a team
of experts including Joseph Lamb, MD (July 2000), The Integrative Medicine
Works, Alexandria, VA;Enrico Liva, ND, RPh (August 2000), Vital Nutrients,
Middletown, CT; Brian T Sanderoff, PD, BS in Pharmacy (March 2000), Clinical
Assistant Professor, University of Maryland School of Pharmacy; President, Your
Prescription for Health, Owings Mills, MD; Ira Zunin, MD, MPH, MBA (July 2000),
President and Chairman, Hawaii State Consortium for Integrative Medicine,
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