One theory holds that oxidative stress makes Alzheimer's disease (AD) worse. Antioxidants should decrease this stress and several agents have shown promise for AD. Three antioxidants, vitamin E, Ginkgo biloba and Salvia officinalis, are discussed below.

• Vitamin E
• Ginkgo biloba
• Salvia officinalis

Vitamin E (1000 international units twice a day) was shown in a placebo-controlled trial to slow loss of cognitive function in patients with Alzheimer's disease. While vitamins can be purchased over-the-counter, any treatment that is effective is likely to have side effects and vitamin E is no exception. Bleeding and upset stomach are the most common side effects. The December 2007 Practice Guideline for the Treatment of Patients with Alzheimer's Disease and Other Dementias states "vitamin E is no longer recommended for the treatment of cognitive symptoms of dementia." If it is used, doses at or below 400 units are suggested.

Ginkgo biloba (sometimes misspelled gingko) is an over-the-counter herbal treatment alleged to improve memory, attention and other thinking functions. Enthusiasm for Ginkgo biloba as a treatment for Alzheimer's disease was based on individual cases and several controlled studies of varied designs. Recently, ginkgo was studied in a 6-week randomized, double-blind, placebo-controlled study of healthy elderly volunteers. There were no significant differences between volunteers receiving ginkgo or placebo as assessed by clinicians, patients, spouses, friends or relatives. Ginkgo was prescribed in the dose recommended by the manufacturer and clinical assessments used standardized tests of memory, learning, attention and concentration, and expressive language. Ginkgo does not have FDA-approval for treatment of AD (as a nutritional supplement, this is not required) and doesn't appear to improve thinking in elderly individuals without Alzheimer's disease. A review done in 2007 concluded: "The evidence that ginkgo has predictable and clinically significant benefit for people with dementia or cognitive impairment is inconsistent and unconvincing" (Cochrane Database System Review 2007, April 18; (2):CD003120). Also, ginkgo has side effects, including increased risk of bleeding.

Salvia officinalis (sage) extract had beneficial effects on mild to moderately severe Alzheimer's disease in a very small, double-blind, placebo-controlled study. These results must be considered preliminary and need to be verified by more extensive research.

Please keep in mind that herbal labels often misrepresent the amount of herbal substance in the bottle. Ginseng, another herbal product, is an example of this problem. An authoritative study in the New England Journal of Medicine (December 19, 2002) found three different products had 11.9%, 220.8% and 327.7% of the amount of ginseng that were indicated on their label!

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