Other ingredients
Huperzine-A
Names you may see: huperzine A HupA Huperzia serrata Chinese club moss
The quick take
Huperzine-A is a compound associated with Chinese club moss that affects acetylcholine signalling.
A closer look
What forms will I see on a label?
Labels may list huperzine A or Huperzia serrata extract. Compare the stated active amount; extract weight alone is not equivalent.
Why people use it
It appears in nootropic and focus formulas marketed for memory, alertness and concentration.
These are common goals and marketing uses. The evidence section below explains what research supports.
What does the evidence tell us?
Research in people with cognitive disorders cannot be assumed to apply to healthy users. Reliable evidence for improved cognitive performance in otherwise healthy people is lacking.
What should I know before using it?
Reported effects include nausea, sweating, dizziness and a slowed heart rate. Seek medical advice before combining it with medicines or other nootropics. Long-term safety is uncertain.
Sources & further reading
Operation Supplement Safety — huperzine A ↗
Content reviewed: September 30, 2026
General educational information. Follow the product label and seek individual advice when needed.