Huperzine A
A naturally occurring alkaloid extracted from Chinese club moss (Huperzia serrata). It powerfully inhibits acetylcholinesterase — the enzyme that breaks down acetylcholine — resulting in significantly elevated acetylcholine levels in the brain. Used in Chinese medicine for centuries and now studied worldwide for Alzheimer's disease.
Dosage
Standard: 50-200 mcg once or twice daily. Due to the long half-life, cycling is recommended (2 weeks on, 1 week off). Do not combine with prescription acetylcholinesterase inhibitors (donepezil, rivastigmine).
Dosages shown are for research reference only. Always consult a qualified healthcare provider.
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Mechanism of Action
Huperzine A is a potent, selective, and reversible inhibitor of acetylcholinesterase (AChE), binding to the enzyme's active site and preventing hydrolysis of acetylcholine to choline and acetate. By blocking AChE, it increases acetylcholine concentration in the synaptic cleft, prolonging activation of muscarinic (M1-M5) and nicotinic receptors. Huperzine A also blocks NMDA glutamate receptors in a non-competitive, use-dependent manner (similar to memantine), binding to the phencyclidine site within the ion channel and protecting neurons from excitotoxic calcium influx. It shows selectivity for the NR2A and NR2B subunits. Additionally, huperzine A has antioxidant properties, scavenging reactive oxygen species and reducing lipid peroxidation. It may enhance NGF signaling.
Regulatory Status
Approved in China for Alzheimer's treatment. Dietary supplement in the US. Research compound in Europe.
Risks & Safety
Common
Nausea, diarrhea, sweating, muscle twitching.
Serious
Cholinergic crisis at high doses (excessive acetylcholine causing muscle weakness, breathing difficulty).
Rare
Blurred vision, slowed heart rate, seizures.
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Research Papers
10Published: October 28, 2021
AI Summary
Huperzine A (HupA), an alkaloid found in the club moss Huperzia serrata, has been used for centuries in Chinese folk medicine to treat dementia. Here, we summarize the neuroprotective effects of HupA on AD, with an emphasis on its interactions with different molecular signaling avenues, such as the Wnt signaling, the pre- and post-synaptic regio...
Published: January 16, 2004
AI Summary
The mechanism of action of huperzine A is suggested to be facilitated through the slow reversible inhibition of acetylcholinesterase. Clinical trials of huperzine A in elderly patients with age-associated memory loss are underway in the US, and a phase II study funded by an NCI grant is being planned.
Published: August 4, 2022
AI Summary
The commercial Ginkgo biloba formulation EGb 761® and Huperzine A, an alkaloid present in the plant Huperzia serrata, have shown in clinical trials to possess cholinergic and neuroprotective activities, including improvement in cognition, activities of daily living, and neuropsychiatric symptoms in AD patients.
Published: November 29, 2022
AI Summary
Unfortunately, the biosynthesis mechanism of HupA has not been well documented. Overall, this review aims to provide valuable insights for complete biosynthesis of Hup A.
Published: October 1, 2024
AI Summary
Huperzine A (Hup A), a natural alkaloid, has demonstrated significant hypoglycemic and anti-inflammatory effects. We aim to investigate the protective effects of Hup A on DN and explore the underlying mechanisms METHODS: We applied STZ induced diabetic rats as DN model and leveraged combination analysis of the transcriptome, metabolome, microbio...
Published: April 15, 2008
AI Summary
Cholinesterase inhibitors may block the degradation of acetylcholine, thus increasing the efficacy of the remaining cholinergic neurons. These properties might qualify Huperzine A as a promising agent for treating dementia (including AD).
Published: October 15, 2019
AI Summary
Abstract too short to summarize.
Published: March 23, 2009
AI Summary
To review the role of huperzine A in the treatment of Alzheimer's disease (AD).
Published: December 2, 2022
AI Summary
Finally, the mechanisms of Huperzine A on AD models were summarized. (3) Conclusions: The outcomes showed that Huperzine A displayed AChE inhibition, ChAT activity enhancement, memory improvement, and Aβ decreasing activity, indicating the disease-modifying effect of Huperzine A.
Frequently Asked Questions
What is Huperzine A used for?
A naturally occurring alkaloid extracted from Chinese club moss (Huperzia serrata). It powerfully inhibits acetylcholinesterase — the enzyme that breaks down acetylcholine — resulting in significantly elevated acetylcholine levels in the brain. Used in Chinese medicine for centuries and now studied worldwide for Alzheimer's disease.
What are the side effects of Huperzine A?
Common: Nausea, diarrhea, sweating, muscle twitching. Serious: Cholinergic crisis at high doses (excessive acetylcholine causing muscle weakness, breathing difficulty). Rare: Blurred vision, slowed heart rate, seizures.
How is Huperzine A administered?
Huperzine A is administered via oral (capsules, tablets). well-absorbed orally..
What is the half-life of Huperzine A?
The half-life of Huperzine A is 10-14 hours.
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