Huperzine A

Scientific Name(s): Huperzia serrata (Thunb.) Trev., Lycopodium serratum (Thunb.).
Common Name(s): Brainmax, Chien Tseng Ta, Club moss, Jin Bu Buan, Memorzine, Neuroflow, Qian Ceng Ta, She Zu Cao, Shi Song

Medically reviewed by Drugs.com. Last updated on Aug 23, 2021.

Clinical Overview

Use

Historically, club moss has been used for the treatment of bruises, strains, swelling, rheumatism, and colds, to relax muscles and tendons, and to improve blood circulation. Because of its anticholinesterase activity, huperzine A, a constituent of the whole plant, has been studied for potential use in treating Alzheimer disease and other CNS disorders; however, there is still insufficient evidence to support its routine use.

Dosing

Huperzine A has been studied at oral dosages of 0.2 to 0.4 mg/day for Alzheimer disease.

Contraindications

Contraindications have not been identified.

Pregnancy/Lactation

Information regarding safety and efficacy in pregnancy and lactation is lacking.

Interactions

None well documented.

Adverse Reactions

In clinical trials, cholinergic adverse reactions have been noted, including hyperactivity, nasal obstruction, nausea, vomiting, diarrhea, insomnia, anxiety, dizziness, thirst, and constipation. One trial reported abnormalities in electrocardiogram (ECG) patterns (cardiac ischemia and arrhythmia).

Toxicology

Symptoms of acute toxicity are similar to those of other cholinergic inhibitors and include muscular tremor, drooling, tears, increased bronchial secretions, and incontinence. No mutagenicity or teratogenicity were found in rodent studies.

Scientific Family

• Lycopodiaceae (club moss)

Botany

Huperzine A is isolated from the club moss Huperzia serrata, also known as Lycopodium serratum Thunb. Distributed worldwide, club moss is found in subtropical zones of the United States and in southern China. It has been extensively cultivated and may be threatened in the wild in China.

Club mosses are primitive, vascular plants that differ from true mosses by having specialized fluid-conducting tissues, but, like mosses, they reproduce by means of spores, which are either clustered into small cones or born in the axils of the small, scale-like leaves. Plants older than 15 years may only grow to 10 cm in height. Some species of Lycopodium are called ground pine or creeping cedar, especially those that resemble miniature hemlocks, with flattened fan-shaped branches often used for Christmas decorations.1, 2 A synonym is Lycopodium serratum Thunb.

History

The use of club moss can be traced back to the Chinese pharmacopoeias of the Tang dynasty as Shi Song, used for the treatment of rheumatism and colds, to relax muscles and tendons, and to improve blood circulation. As Qian Ceng Ta, it has been used for the treatment of bruises, strains, and swelling, and, more recently, for organophosphate poisoning, myasthenia gravis, and schizophrenia. The study of the chemistry and pharmacology of the plant and its alkaloids gained momentum in the 1980s from Chinese scientists.3, 4, 5, 6

Chemistry

A review of the chemical composition of club moss has been published. The plant contains mainly alkaloids, triterpenes, flavones, and phenolic acids. Four major structural classes of Lycopodium alkaloids have been described, including lycopodine, lycodine (to which huperzine A belongs), fawcettimines, and others.4 The yield of huperzine A from H. serrata is reported to be approxim...