Huperzine A
Huperzine A slows the breakdown of acetylcholine. In the only placebo-controlled study in healthy adults, 100 to 200 micrograms did inhibit the enzyme, while cognitive performance did not improve.
What the research shows
No sound research in humans.
Morasch (2015) gave healthy adults a single dose of 100 or 200 micrograms, confirmed that the enzyme acetylcholinesterase was inhibited, and found no improvement on any cognitive task; the study was paid for by the US Army. The Cochrane review by Yue (2012) searched for trials in mild cognitive impairment and found not a single study that met the criteria. Yang (2013) pooled 20 Chinese trials covering 1823 Alzheimer's patients that did show gains on the MMSE, with a high risk of bias in most trials and in a group that has nothing in common with a healthy athlete.
Who it makes sense for: Nobody looking for sharper focus. The substance has been tested at exactly this dose in healthy adults and produced no improvement at all.
How we weigh evidenceClinical dosage
Origin
NaturalHuperzine A is extracted from the Chinese club moss Huperzia serrata, also known as toothed clubmoss. It has been used for centuries in traditional Chinese medicine (Qian Ceng Ta). In supplements as purified extract.
Safety
An acetylcholinesterase inhibitor, so dose it with respect. Studies use 50 to 200 micrograms per day. The positive results come from research in Alzheimer's and vascular dementia; the Cochrane review on mild cognitive impairment found no usable study at all. Side effects at higher doses are nausea, diarrhoea and muscle twitching. Do not combine with anticholinergics or other cholinesterase inhibitors.
For comparison
Huperzine A works similarly to Alzheimer's medications (like donepezil), but at much lower doses. It inhibits the breakdown of acetylcholine, making more available for your brain. The dose in pre-workouts (50-200mcg) is tiny compared to pharmaceutical agents.
Dosage by weight and gender
The typical huperzine A dose is 50-200mcg per day (note: micrograms, not milligrams). Body weight plays a limited role. There are no gender-specific recommendations. Cycling (4 weeks on, 1 week off) is often recommended due to the long half-life. Don't use daily for extended periods without breaks.
Frequently asked questions
What does huperzine A do?
Huperzine A may improve mental focus and memory by inhibiting the breakdown of acetylcholine. In pre-workouts it's added for a sharper mind-muscle connection. Sun et al. (1999) found improvements in memory and learning ability in young students.
Is huperzine A dangerous?
At the low doses in pre-workouts (50-200mcg) the risk is limited. However, it's an active compound affecting acetylcholine levels. Don't combine with other cholinergic agents. Take breaks with long-term use and consult a doctor if you use medications.
How much huperzine A per day?
50-200mcg (micrograms) per day. Most pre-workouts contain 100-200mcg. Take it cyclically: 4 weeks on, 1 week off. The half-life is long (10-14 hours), so it accumulates with daily use.
Scientific sources
The clinical dosages on this page are based on peer-reviewed research.
- Physiological and neurobehavioral effects of cholinesterase inhibition in healthy adultsMorasch KC et al. (2015)Funded by: Uitgevoerd door het Walter Reed Army Institute of Research en het US Army Medical Research and Materiel Command, dus overheidsonderzoek zonder betrokken fabrikant.
- Huperzine A for mild cognitive impairmentYue J et al. (2012)Funded by: Cochrane-review van het West China Hospital, Sichuan University; de auteurs verklaren geen belangenverstrengeling.
- Huperzine A for Alzheimer's disease: a systematic review and meta-analysis of randomized clinical trialsYang G et al. (2013)Funded by: Uitgevoerd aan het Centre for Evidence-based Chinese Medicine van de Beijing University of Chinese Medicine; PubMed toont een lege belangenverklaring.
Pre-workouts with Huperzine A
No products found with this ingredient
We keep the dosages and values on this page as accurate as possible based on selected studies. New research may change these values. Nothing on this page is medical advice. If you have any doubts, always consult a doctor.