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Huperzine-A

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Subjective Effects
Interactions
Tolerance
Huperzine-A molecule structureHuperzine-A molecule structure
Open in Piru

Huperzine-A is a naturally occurring1 sesquiterpene alkaloid2 tentatively classified as a nootropic.3 It occurs in Huperzia serrata and several related plant species4 and was first isolated in 1983. Huperzia serrata has been used in Chinese folk medicine for centuries to treat swelling, fever, and blood disorders.5 Huperzine-A is marketed as a nutritional supplement for memory and concentration enhancement.6

Dosage & Duration

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Dosage

Doses are population estimates that vary widely between individuals.

Threshold~50 µg
Light50-75 µg
Moderate75-150 µg

Insufflated doses are generally equivalent to oral doses. Huperzine-A is commonly administered once daily and cycled, with users typically discontinuing use after two to four weeks before resuming. The optimal dosing regimen has not been established.

Subjective Effects

Subjective Effects not written up yet

Pharmacology

Pharmacodynamics

Huperzine A potently and reversibly inhibits acetylcholinesterase7, reducing acetylcholine breakdown and increasing its availability. It also weakly antagonizes NMDA receptors, but its low affinity makes significant NMDA receptor blockade unlikely at clinically relevant concentrations in humans.

Pharmacokinetics

Huperzine A readily crosses the blood-brain barrier.8

Metabolitesnone documented yet

Interactions

Interactions not written up yet

An unlisted combination is an unknown one, not a safe one. Check a dedicated combination chart before mixing.

Check TripSit

Tolerance

Tolerance not written up yet

Harm Potential

Toxicity

Cardiovascular

May contribute to bradycardia (decreased heart rate), particularly when combined with other agents that slow heart rate such as beta-blockers.

Gastrointestinal

Mild cholinergic side effects including nausea, vomiting, and diarrhea may occur at typical doses.

Neuromuscular

Slight muscle twitching and slurred speech may occur as cholinergic side effects.

Secretory

Hypersalivation and sweating may occur as mild cholinergic effects.

History & Culture

Huperzia serrata had been used in Chinese folk medicine for centuries to treat swelling, fever, and blood disorders. Huperzine A was first isolated from the plant in 1983.9…

Legality

By Country

Not scheduled1
United States flagUnited StatesNot scheduled

References

Citations

  1. Plant alkaloids as drug leads for Alzheimer's disease. Neurochemistry International (2015). https://doi.org/10.1016/j.neuint.2015.07.0181
  2. Huperzinea: Pharmacological and Therapeutic Potential. Pharmacognosy Communications (2020). https://doi.org/10.5530/pc.2020.4.311
  3. Huperzine A. Drugs in R&D (2004). https://doi.org/10.2165/00126839-200405010-000091
  4. Validation of a Microscale Extraction and High Throughput UHPLC-QTOF-MS Analysis Method for Huperzine A in Huperzia: Microscale UHPLC-MS Analysis of Huperzine A. Phytochemical Analysis (2012). https://pmc.ncbi.nlm.nih.gov/articles/PMC33378871
  5. Dictionary of Nutraceuticals and Functional Foods. CRC Press / Taylor & Francis (2006). https://cannalib.eu/wp-content/uploads/2023/08/Dictionary-of-nutraceuticals-and-functional-foods-2006.pdf1
  6. Huperzine A: Dietary Supplements for Brain Health. Operation Supplement Safety (2024). https://www.opss.org/article/huperzine-dietary-supplements-brain-health1
  7. Efficacy of huperzine in preventing soman-induced seizures, neuropathological changes and lethality. Fundamental & Clinical Pharmacology (1997). https://doi.org/10.1111/j.1472-8206.1997.tb00200.x12
  8. Huperzine A and Its Neuroprotective Molecular Signaling in Alzheimer’s Disease. International Journal of Molecular Sciences (2021). https://pmc.ncbi.nlm.nih.gov/articles/PMC85875561
  9. Huperzimine, a novel Lycopodium alkaloid from Huperzia serrata. ResearchGate, Canadian Science Publishing publisher preview (2014). https://doi.org/10.1139/cjc-2013-052012
  10. Huperzine A for Alzheimer’s Disease: A Systematic Review and Meta-Analysis of Randomized Clinical Trials. PLOS ONE (2013). https://doi.org/10.1371/journal.pone.00749161

Article Status

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