← Back
3Medicinal

Huperzine A

Also sold as Huperzia serrata

A cholinesterase inhibitor — pharmacologically active, not benign.

3TrustedSupp Tier System™ · Tier 3Take as a defined course
Check before you startThis one has documented interactions with medication classes where the consequences are serious. If you take any prescription medicine, run it past a pharmacist before starting.

How long to take it

Short courses only, with medical oversight.

Who it's actually for

Not a casual nootropic. Discuss with a doctor.

Safe upper limit

Unverified
No formal limit; 50–200 mcg daily. Treat as a drug
Genuinely drug-like. Can cause slow heart rate, nausea, and cholinergic side effects, and stacks dangerously with dementia medication.
No source attached yet. Treat this as a starting point, not a citation, until reviewed.

Interactions to know about

  • Anti-seizure medicationPhenytoin, valproate, carbamazepine, lamotrigine
  • Sedatives / sleep medicationBenzodiazepines, zopiclone, zolpidem, opioids
  • Blood pressure medicationBeta blockers, calcium channel blockers, ACE inhibitors
  • Any other prescription medicineCatches broad enzyme and absorption effects

Other supplements:

Run your full list through the interaction check.

Practical notes

  • Never combine with donepezil or similar dementia drugs.
  • Avoid with slow heart rate, asthma, or epilepsy.