[3] Huperzine A has been investigated as a treatment for neurological conditions such as Alzheimer's disease, but a 2013 meta-analysis of those studies concluded that they were of poor methodological quality and the findings should be interpreted with caution.

[5] Slight muscle twitching and slurred speech might also occur, as well as excessive saliva excretion and sweating.

The use of huperzine A during pregnancy and lactation is not recommended due to the lack of sufficient safety data.

[17] Huperzine A may have additive effects if taken with drugs causing bradycardia, such as beta-blockers,[18] which may decrease heart rate.

Toxicology studies show huperzine A to be non-toxic even when administered at 50-100 times the human therapeutic dose.