Huperzine-A: The Proven Therapeutic Treatment for Memory Loss

Health care professionals are sounding the alarm that Alzheimer’s disease will be an epidemic of astronomical proportions for the Baby Boom generation. According to a recent report released by Boston University’s School of Medicine, women over 55 face a one in four lifetime risk of developing Alzheimer’s disease, and men a one in six chance.2 But here’s some good news.

Huperzine-A, an alkaloid extracted from a Chinese moss, Huperzia serrata, is showing great promise as a therapeutic treatment for Alzheimer’s disease and other memory loss disorders. It has a long history of use in traditional Chinese medicine.3 It has been approved as a drug in China to treat Alzheimer’s disease and other age-associated memory impairments, and is marketed in the U.S. as a dietary supplement.4 It also helps improve memory and learning in adolescent students.

How does it work?

First, it’s important to understand how acetylcholine works. This messenger molecule is the most abundant and essential neurotransmitter in the brain that is responsible for numerous functions, including many related to cognition and memory. Acetylcholine is released into the synapse, or space between two nerve cells, where it stimulates the transfer of nerve impulses from one nerve cell to another. After the nerve impulse is transmitted, acetylcholinesterase—an enzyme that is found between nerve endings—breaks down acetylcholine into choline and acetate, and the nerve signal ends.

Loss of acetylcholine function is a primary feature of several types of brain dysfunction, including Alzheimer’s disease. In Alzheimer’s disease and senile dementia, acetylcholine is destroyed too quickly, and consequently the nerve impulse is either too weak to be received or it is incompletely transmitted between nerve cells. A shortage of acetylcholine is considered the most common cause of memory loss, decreased learning ability and intelligence. Additionally, the greatest amount of damage in the Alzheimer’s brain is in the cells using acetylcholine.5 Huperzine-A inhibits the activity of acetylcholinesterase, so the breakdown of acetylcholine is slowed and the strength and duration of the nerve impulse is improved. Fortunately, based on scientific studies in both human and animal models, we now know that Huperzine-A makes more acetylcholine available for better brain functioning, and that it is a promising supplement for reversing and/or slowing down Alzheimer’s disease and other brain disorders. Animal studies have also shown that Huperzine can protect against environmental poisoning and that it reduces glutamate-induced cell death.6

Scientific studies

In a 1995 double-blind, placebo controlled study at Zhejiang Medical University, in Hangzhou, China, 50 Alzheimer’s patients received 200 mcg of Huperzine-A and 53 received a placebo for 8 weeks. All the patients were evaluated with several memory exams, including the Wechsler memory scale and the mini-mental state examination scale. At the end of the study, about 58% (29/50) of the patients treated with Huperzine-A showed significant improvements in their memory, cognitive, and behavioral functions versus only 36% of those receiving the placebo. There were no adverse side effects reported, and the researchers said, “Huperzine is a promising drug for symptomatic treatment of Alzheimer’s disease.” 7

In a more recent study, Huperzine-A was tested on 202 mild to moderate Alzheimer’s patients at the Peking Medical College Hospital in Beijing, China. One group was given 400 mcg of Huperzine-A per day for 12 weeks, and the other group was given a placebo. All patients were assessed with tests that evaluated their cognitive function, daily life activity and non-cognitive disorders, such as muscle control. The group treated with Huperzine-A showed remarkable improvement in cognition, behavior and mood, in comparison to the placebo group. There were no side effects except for a few reports of very mild insomnia and water retention in a few patients, and these effects were transient.8

Huperzine-A protects against free radicals

In addition to its acetylcholine enhancing effects, Huperzine-A was found to protect against free radical-induced cell toxicity in lab tests.9 This is significant because many modern diseases are believed to be the result of free radical damage. Huperzine has also been shown to dramatically decrease the abnormally elevated free radical activity in both the brain of old animals10, and the blood of Alzheimer’s victims11 . This protective effect has been noted by scientists to be a significant additional benefit of Huperzine-A, beyond its acetylcholine enhancing effect.

Reverses effects of amnesia

Scopolamine is a class of drugs that can induce amnesia, which works by interfering with acetylcholine. A study performed on young and old monkeys given the drug showed that Huperzine-A reversed the deficits in performance and memory that result from scopolamine, suggesting that Huperzine-A may benefit cognitive impairments in patients with Alzheimer’s disease and other memory disorders.12

Adolescent students also benefit from Huperzine-A

In a study to determine the effects of Huperzine-A on memory and learning in adolescents, Chinese researchers selected 34 matched pairs of normal middle school students whose only complaints were of poor memory and difficulty in learning.

In a double-blind trial, one member of each pair was given 100 mcg of Huperzine-A twice daily for four weeks, while the other member received the placebo. The students’ memory quotients were measured before and after the trial, and their academic performance in their Chinese, English, and mathematics lessons was also monitored. At the end of the study, the Huperzine-A group scored significantly higher than the control group on standard memory tests. They also did significantly better in their Chinese and English lessons. No side effects of any kind were noted.13

The advantages of Huperzine-A over prescription drugs

Animal research suggests that Huperzine-A’s ability to preserve acetylcholine may be greater than that of the two FDA-approved Alzheimer’s drugs tacrine and donepezil. Like these drugs, Huperzine-A works by disrupting acetycholinesterase, yet it seems to do it more effectively and with fewer side effects.14 Huperzine-A has a longer duration of action, is absorbed more quickly, penetrates the brain more rapidly, has little or no side effects, and does not produce liver toxicity.15

Additionally, in a study comparing the toxicity of Huperzine-A versus tacrine (the Alzheimer’s drug commonly known as Cognex™) on the liver of laboratory animals, only tacrine was found to cause liver toxicity.16

What is the suggested dosage?

The doses of Huperzine-A used in clinical studies range from 50 micrograms to 400 micrograms daily.

An important consideration is the quality and form of the Huperzine product you purchase. While Huperzine-A in a highly purified form has been used in the vast majority of research, Huperzine-A occurs naturally in extremely small quantities in the moss it is extracted from.

As you can imagine, extracting pure Huperzine-A is extremely difficult and expensive, while crude moss extracts cost MUCH less to manufacture. In fact, pure Huperzine-A is the most expensive dietary supplement ingredient in the world!

Most products on the market are simply crude moss extracts that contain only a low percentage of Huperzine-A. Additionally, these extracts naturally contain many other alkaloids related to Huperzine-A that have not been studied in humans or proven safe.17 These products may be labelled as containing only Huperzine-A, but actually are giving you a variety of these related alkaloids from crude moss extracts, rather than a known amount of actual Huperzine-A.

The safety of pure Huperzine-A has been established in numerous human clinical and laboratory studies, but the safety of crude moss extracts containing a low percentage of Huperzine-A has not. Because all of the impressive studies have used pure Huperzine-A, this is the preferred form of Huperzine for supplementation.

How safe is Huperzine-A?

Medications that prevent acetylcholine breakdown often produce side effects, including nausea, vomiting, excess saliva and tear production, and sweating. However, while dizziness was reported in a few people in one study, and mild insomnia and water retention in another, no severe side effects have been reported in human trials using Huperzine-A. The most common side effect is usually mild nausea, and all of these minor side effects are dose related and can be avoided by slowly increasing the daily dosage of Huperzine-A. However, if side effects continue to occur, reduce dosage until side effects disappear.

Huperzine should not be used by children, pregnant women, or nursing mothers.

Brain boosters with significant research

As a treatment for Alzheimer’s disease, dementia, age-associated memory impairment, and senile memory disorders, Huperzine-A has shown some impressive results with virtually no side effects. With the ensuing epidemic of memory related disorders, it’s important to do everything we can to protect our delicate brain cells and prevent age-related declines in neurotransmitters and free radical protection. In addition to Huperzine-A, Vitamins C and E, ginkgo biloba, phosphatidylserine, vinpocetine, acetyl-l-carnitine, lipoic acid, bacopa, pregnenolone, and glycerylphosphorylcholine (GPC) are among the growing list of safe and effective therapeutic agents shown to improve memory and protect the brain from the devastating effects of free radical damage and diseases such as Alzheimer’s.


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