Huperzine A is a chemical compound that can be isolated from the plant Huperzia serrata (Chinese club moss), a traditional Chinese remedy used for contusions, strains, swelling, and schizophrenia. It can also be made in a laboratory. Huperzine A is commonly listed as “Huperzia serrata extract,” “HupA,” or “Chinese club moss” on dietary supplement product labels. It is often marketed for brain health and cognitive performance, with claims of enhanced brain power, memory, alertness, attention, concentration, and focus.

No reliable scientific evidence supports the use of huperzine A to enhance cognitive performance, and its overall safety is not yet understood.

Is it an approved dietary supplement ingredient?

Although it is marketed in the U.S. as a dietary supplement ingredient, huperzine A is an approved drug in some other countries. For example, huperzine A is available in most hospitals in China and is used to “treat” Alzheimer’s disease. In the U.S., however, it is unclear whether huperzine A can be legally marketed as a dietary supplement.

Is huperzine A safe or effective as a dietary supplement?

Preliminary evidence suggests huperzine might have beneficial effects on cognitive function among Alzheimer’s disease patients, but more research is needed to establish this conclusively. Some companies have been marketing “supplements” containing huperzine A with illegal claims that their products can “treat” Alzheimer’s. Currently, the Alzheimer’s Association recommends not taking huperzine A, especially with prescription drugs, because the combination could increase the risk of serious side effects. Commonly reported adverse effects include decreased heart rate, nausea, vomiting, diarrhea, dizziness, sweating, blurred vision, and insomnia. Overall, safety data are lacking and long-term use is not well understood.

To date, no studies have examined the safety or effectiveness of huperzine A for cognitive performance in otherwise healthy individuals.

Can Military Service Members use huperzine A?

Huperzine A is not prohibited for use by DoD members, and it will not cause a positive result on a routine military drug test. However, given the limited evidence of its safety, we advise caution with products that contain this ingredient.

In addition, some dietary supplement products containing huperzine A include substances prohibited for use. Consuming such ingredients could put your health, career, or both at risk. In some cases, these ingredients might not be listed on a product’s label, so you could consume prohibited ingredients unknowingly. Using products that have been third-party certified can help you avoid this possibility.


Updated 11 June 2020


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