Named Bioactive Compounds · Compound
Galanthamine
Moderate Evidencealkaloid2 PubMed Studies
Hermetica Superfood Encyclopedia
Galanthamine is a tertiary alkaloid derived from plants such as Galanthus nivalis (snowdrop) and Narcissus species that acts as a reversible, competitive acetylcholinesterase inhibitor and allosteric potentiating ligand at nicotinic acetylcholine receptors. It is clinically approved for mild-to-moderate Alzheimer's disease, improving cognitive scores by 3–4 points on the ADAS-cog scale across multiple large randomized controlled trials.
Galanthamine is a naturally occurring alkaloid extracted from bulbs of Amaryllidaceae family plants, including snowdrop (Galanthus woronowii), daffodil (Narcissus pseudonarcissus), and snowflake (Leucojum aestivum). It is obtained through solvent extraction with ethanol or methanol, followed by chromatographic purification, yielding pharmaceutical-grade product with molecular formula C17H21NO3.
Multiple large-scale randomized controlled trials demonstrate galanthamine's efficacy, including studies with 636 patients (PMID 10881250), 978 patients (PMID 10881251), and a landmark 2-year trial with 2,045 patients (PMC3937252) showing 34% less cognitive decline. A 2024 Cochrane meta-analysis (PMID 39498781) confirmed that 16-24 mg/day doses consistently slow cognitive decline versus placebo.
Clinical studies used immediate-release oral tablets of galanthamine hydrobromide, escalated over 4-8 weeks to maintenance doses of 16-24 mg/day (typically 8 mg twice daily). Maximum studied dose is 32 mg/day, though this showed higher gastrointestinal side effects. Only pharmaceutical-grade standardized forms (>98% purity) have been clinically tested. Consult a healthcare provider before starting any new supplement.
Galanthamine (C₁₇H₂₁NO₃, MW 287.35 g/mol) is a tertiary alkaloid, not a nutritional supplement, and therefore lacks a conventional nutritional profile of macronutrients, vitamins, minerals, fiber, or protein. Key pharmacological and biochemical details: • Bioactive compound: Galanthamine itself is the sole active pharmacological agent — a selective, competitive, and reversible acetylcholinesterase (AChE) inhibitor (IC₅₀ ~0.35–0.50 µM) and an allosteric potentiating ligand (APL) at nicotinic acetylcholine receptors (nAChRs), particularly α7 subtype. • Natural source concentrations: Found in Amaryllidaceae plants — Galanthus nivalis (snowdrop) bulbs contain approximately 0.05–0.1% w/w galanthamine; Narcissus pseudonarcissus (daffodil) bulbs ~0.01–0.05% w/w; Leucojum aestivum (summer snowflake) bulbs ~0.1–0.2% w/w, which is the primary commercial botanical source. Lycoris radiata also contains trace amounts (~0.01%). • Pharmaceutical dosing: Typical therapeutic doses are 16–24 mg/day (given as 8–12 mg twice daily in immediate-release form, or 16–24 mg once daily in extended-release form). The starting dose is 8 mg/day, titrated upward every 4 weeks. • Bioavailability: Oral bioavailability is approximately 88–100% with rapid and nearly complete gastrointestinal absorption. Time to peak plasma concentration (Tmax) is ~1 hour for immediate-release and ~4.5–5 hours for extended-release formulations. Plasma protein binding is approximately 18%, indicating high free-fraction availability. Volume of distribution is ~175 L. • Metabolism: Primarily hepatized via CYP2D6 and CYP3A4 cytochrome P450 enzymes. Major metabolites include O-desmethylgalanthamine, galanthamine-N-oxide, and epigalanthamine — none with clinically significant AChE inhibition. Terminal elimination half-life is approximately 7–8 hours. Approximately 20–25% is excreted unchanged in urine. CYP2D6 poor metabolizers exhibit ~35% higher AUC. • Additional bioactive properties: Exhibits weak antioxidant activity (ORAC data limited); demonstrates anti-inflammatory effects via α7 nAChR-mediated suppression of TNF-α and IL-6 release (cholinergic anti-inflammatory pathway activation); no significant caloric, vitamin, mineral, or fiber content as it is administered as a pure pharmaceutical compound (typically as galanthamine hydrobromide salt, MW 368.27 g/mol). • No macronutrient content: 0 g protein, 0 g fat, 0 g carbohydrate, 0 g fiber, 0 kcal per dose. Contains no vitamins or minerals in therapeutic formulation beyond inactive excipients.
Galanthamine reversibly inhibits acetylcholinesterase (AChE) at the synaptic cleft, preventing the breakdown of acetylcholine and increasing its availability at muscarinic and nicotinic receptors in cortical and hippocampal circuits. It simultaneously acts as an allosteric potentiating ligand (APL) at nicotinic acetylcholine receptors (nAChRs), specifically the α4β2 and α7 subtypes, sensitizing them to acetylcholine without directly activating them. This dual mechanism enhances cholinergic neurotransmission more robustly than AChE inhibition alone, potentially also promoting neuroprotection via α7 nAChR-mediated reduction of amyloid-beta toxicity.
Multiple large randomized controlled trials (RCTs) with sample sizes ranging from 636 to 2,045 participants have demonstrated that galanthamine at 16–24 mg/day produces statistically significant improvements of 3–4 points on the ADAS-cog scale compared to placebo in patients with mild-to-moderate Alzheimer's disease. A 2-year RCT showed 24% less decline in activities of daily living (ADL) scores in the galanthamine group relative to placebo, indicating functional as well as cognitive benefit. Evidence for its cognitive effects is rated strong based on consistency across trials conducted by independent groups; evidence for slowing disease progression is more limited and requires further long-term study. Galanthamine has not demonstrated robust efficacy in vascular dementia or other non-Alzheimer's dementias in meta-analyses.
The most common adverse effects of galanthamine are dose-dependent gastrointestinal symptoms including nausea (up to 30% of users), vomiting, diarrhea, and anorexia, which are minimized by titrating slowly from 8 mg/day to the target dose of 16–24 mg/day over several weeks. It carries a risk of bradycardia and should be used with caution in patients with sick sinus syndrome, cardiac conduction disorders, or those taking beta-blockers, digoxin, or other drugs that slow heart rate. Galanthamine is contraindicated with other cholinesterase inhibitors (e.g., donepezil, rivastigmine) due to additive cholinergic toxicity risk, and concurrent use of strong CYP2D6 or CYP3A4 inhibitors such as paroxetine, ketoconazole, or erythromycin can significantly raise galanthamine plasma levels. It is classified FDA Pregnancy Category B based on animal data; safety in human pregnancy and lactation has not been established and its use is generally avoided in these populations.
