Harmine

Overview

Harmine is a naturally occurring β-carboline alkaloid and a principal harmala alkaloid found in Banisteriopsis caapi and Peganum harmala (Syrian rue). It is psychoactive and is traditionally encountered in ayahuasca preparations, where harmine contributes monoamine-oxidase-A (MAO-A) inhibition. The evidence base for therapeutic applications is predominantly preclinical; harmine is not an established self-treatment or general clinical medicine.

Alkaloid class

• Class: β-carboline / indole alkaloid; specifically a methoxy-substituted, aromatic β-carboline.
• Related harmala alkaloids: harmaline and tetrahydroharmine (THH). Harmine is more oxidized and aromatic than harmaline and THH.
• Chemical identity: harmine; commonly reported molecular formula C₁₃H₁₂N₂O and molecular weight approximately 212.25 g/mol. The free base is distinct from harmine hydrochloride and other salts.

Structure

Harmine contains a fused pyrido[3,4-b]indole (β-carboline) ring system with:

• an indole-like nitrogen;
• a ring nitrogen capable of protonation;
• an aromatic, planar conjugated system;
• a methoxy substituent, conventionally designated 7-methoxy-β-carboline.

The aromatic planarity and nitrogen-containing ring system are relevant to DNA/enzyme interactions and CNS activity. Structure–activity findings from analogues should not be assumed to predict the safety or clinical behavior of harmine itself.

Botanical sources

• Banisteriopsis caapi (Malpighiaceae): woody Amazonian vine used in ayahuasca; contains harmine, harmaline, THH, and other constituents. Alkaloid concentrations vary substantially by plant, tissue, preparation, and age.
• Peganum harmala (Nitrariaceae): Syrian rue; seeds and other tissues contain harmine, harmaline, and related β-carbolines. Seeds are pharmacologically potent and composition is variable.
• Other reported plants: β-carbolines, including harmine or related compounds, occur in additional taxa, but identification and concentration require analytical confirmation.

Botanical source does not establish dose, purity, identity, or safety. Commercial and home preparations may contain multiple alkaloids, contaminants, or highly variable concentrations.

Mechanisms

Mechanisms are context- and dose-dependent, and several proposed actions remain preclinical:

• Reversible MAO-A inhibition: increases the potential for elevated serotonin, norepinephrine, and dopamine signaling. This is central to the traditional pharmacology of harmala preparations.
• CNS activity: may contribute to psychoactive, anxiogenic or anxiolytic, cognitive, and antidepressant-like effects in experimental models. Human effects are variable and not equivalent to animal findings.
• Enzyme and kinase interactions: reported effects include inhibition or modulation of DYRK1A/DYRK1B and other signaling pathways; selectivity and clinically relevant exposure remain unresolved.
• Cellular stress and proliferation pathways: in vitro studies report effects involving cell-cycle arrest, apoptosis, DNA interactions, ROS, p53, Akt/FAK, telomerase, angiogenesis, and autophagy. These findings do not demonstrate anticancer efficacy in humans.
• Inflammatory and neuroimmune pathways: experimental studies report modulation of NF-κB, NLRP3 inflammasome, astrocytic function, glutamate transport, and inflammatory mediators.
• Antimicrobial/antiparasitic activity: antiviral and antimalarial effects have been reported in laboratory or animal systems; these are investigational and do not replace standard treatment.

Clinical pattern relevance

Traditional and psychoactive pattern

Harmine-containing preparations may produce altered perception, emotional intensification, dreamlike imagery, nausea, vomiting, tremor, dizziness, sedation or stimulation, and changes in heart rate or blood pressure. Effects depend on dose, route, preparation, co-administered substances, and individual susceptibility.

MAO-A interaction pattern

Because harmine can inhibit MAO-A, a preparation may amplify monoaminergic drugs and supplements. This is especially relevant to people taking antidepressants, stimulants, serotonergic analgesics, migraine medicines, or other psychoactive agents. The combination can produce agitation, autonomic instability, hyperreflexia, clonus, fever, confusion, or seizures.

Research pattern

Preclinical literature suggests possible relevance to depression-like behavior, memory, neuroinflammation, bone remodeling, cardiovascular remodeling, fibrosis, infection, and cancer biology. These observations are hypothesis-generating only. No section of this note should be read as evidence that harmine treats depression, cancer, infection, cardiovascular disease, bone disease, or organ injury in humans.

Red-flag presentation

After exposure, urgent evaluation is warranted for severe agitation or confusion, high fever, sweating, rigidity, clonus, seizures, chest pain, fainting, severe hypertension or hypotension, persistent vomiting, jaundice, or suicidal/psychotic symptoms.

Safety considerations

• Interaction risk: avoid unsupervised combination with serotonergic or sympathomimetic drugs, MAO inhibitors, many antidepressants, stimulants, dextromethorphan, tramadol, meperidine, linezolid, triptans, and serotonergic supplements. Medication washout periods vary; obtain clinician or pharmacist guidance rather than relying on a fixed interval.
• Psychiatric risk: avoid or use extreme caution with personal or family history of bipolar disorder, psychosis, mania, or severe anxiety; psychoactive effects may precipitate destabilization.
• Cardiovascular and neurologic risk: caution with uncontrolled hypertension, arrhythmia, seizure disorders, stroke risk, or significant autonomic disease.
• Pregnancy and lactation: avoid because reproductive and infant safety are not established and MAO-A/psychoactive effects may be consequential.
• Hepatic and renal disease: use is not established; impaired clearance or preparation-specific toxicity may increase risk.
• Toxicology: concentrated extracts and seeds are not equivalent to dilute traditional preparations. Dose-response data are unreliable across products. Do not infer a safe dose from an extraction video or animal study.
• Adverse effects: nausea, vomiting, dizziness, tremor, sedation, insomnia, confusion, ataxia, visual changes, blood-pressure changes, tachycardia, and seizures are possible. Hepatic injury and other toxicities require medical assessment if symptoms occur.
• Regulatory status: legal status and product quality vary by jurisdiction. Testing for identity, alkaloid content, adulterants, and contaminants is often inadequate.
• Clinical evidence limitation: most disease-specific claims below derive from cell culture or animal studies; human pharmacokinetics, therapeutic index, and long-term safety remain insufficiently characterized.

Videos

Extracting Harmine and Harmaline from Peganum Harmala (Syrian Rue seeds)

Extracting Harmala Alkaloids from Syrian Rue (Peganum Harmala) Harmine/Harmaline PT.1

How to Reduce Harmaline to Tetrahydroharmine (Make your own THH)

Safety note: Extraction and reduction demonstrations are not dosing or safety guidance. They may involve corrosive reagents, toxic solvents, fire hazards, concentrated psychoactive alkaloids, and chemically contaminated products.

Articles/Studies

General pharmacology and pharmacokinetics

• Syrian Rue Extraction
• Blood levels and urinary excretion of harmine and its metabolites in man and rats

Bones

• Harmine alleviates titanium particle-induced inflammatory bone destruction.
• Harmine, a β-carboline alkaloid, inhibits osteoclast differentiation and bone resorption in vitro and in vivo.
• Harmine has bone anabolic effects and may be useful for the treatment of bone-decreasing diseases and bone regeneration.
• Harmine may provide potential therapeutic targets for bone loss diseases.

Depression

• Chronic administration of harmine elicits antidepressant-like effects and increases BDNF levels in rat hippocampus.
• Harmine produces antidepressant-like effects via restoration of astrocytic functions.

Cancer

• The beta-carboline alkaloid harmine inhibits BCRP and can reverse resistance to the anticancer drugs mitoxantrone and camptothecin in breast cancer
• Antitumor agents 201.1 Cytotoxicity of harmine and β-carboline analogs
• Harmine hydrochloride triggers G2/M cell cycle arrest and apoptosis in HCT116 cells.
• Anticancer activities of harmine by inducing a pro-death autophagy and apoptosis in human gastric cancer cells
• Harmine induces apoptosis in human SGC-7901 cells
• Harmine induces apoptosis in HepG2 cells via mitochondrial signaling pathway.
• Harmine inhibits angiogenesis and suppresses tumour growth through activation of p53 in endothelial cells.
• Harmine inhibits cell cycle arrest and mitochondrial pathway-mediated cellular apoptosis in SW620 cells.
• Harmine might be a promising herbal medicine in the therapy of thyroid cancer.
• Harmine hydrochloride inhibits Akt phosphorylation and depletes the pool of cancer stem-like cells of glioblastoma.
• Harmine inhibits telomerase activity of MCF-7 cells
• The impact of harmine hydrochloride on growth, apoptosis and migration, invasion of gastric cancer cells.
• Improving anti-tumor outcomes for colorectal cancer therapy through in situ thermosensitive gel loading harmine.
• Structure-activity insights of harmine targeting DNA, ROS inducing cytotoxicity with PARP mediated apoptosis against cervical cancer, anti-biofilm formation.
• Harmine inhibits the proliferation and migration of glioblastoma cells via the FAK/AKT pathway.
• Harmine inhibits breast cancer cell migration and invasion by inducing the degradation of Twist1.
• Harmine hydrochloride mediates the induction of G2/M Cell cycle arrest in breast cancer cells.
• Harmine reinforces the effects of regorafenib on suppressing cell proliferation and inducing apoptosis in liver cancer cells.

Cardiovascular

• Harmine alleviates atherogenesis by inhibiting disturbed flow-mediated endothelial activation via protein tyrosine phosphatase PTPN14 and YAP.
• Harmine is an effective therapeutic small molecule for the treatment of cardiac hypertrophy.
• Harmine alleviated sepsis-induced cardiac dysfunction.

Hepatoprotective

• Harmine suppresses collagen production in hepatic stellate cells by inhibiting DYRK1B.

Herpes

• Harmine blocks herpes simplex virus infection.

Malaria

• Harmine is a potent antimalarial targeting Hsp90 and synergizes with chloroquine and artemisinin.

Memory

• Harmine treatment enhances short-term memory in old rats.

Neuroprotective

• Harmine may exert neuroprotective effects by synergistically reducing excitotoxicity and inflammation following traumatic brain injury.
• Harmine mediated neuroprotection via evaluation of glutamate transporter 1 in a rat model of global cerebral ischemia.
• Harmine ameliorates cognitive impairment by inhibiting NLRP3 inflammasome activation.

Periodontal

• Harmine promotes periodontal ligament cell-induced tissue regeneration.

Renoprotective

• Harmine protects mercuric chloride kidney-induced injury by antioxidant activity in male mice: a biochemical and histological study.

Evidence appraisal

• Human clinical evidence: limited and insufficient to establish efficacy or a therapeutic dose.
• Animal evidence: useful for hypothesis generation but not directly predictive of human benefit or safety.
• Cell/in-vitro evidence: often uses concentrations that may not be achievable safely in humans and may not reflect metabolism or bioavailability.
• Source quality: prioritize primary peer-reviewed studies and PubMed records; treat secondary summaries and extraction resources as supplementary.

Educational reference only; not medical advice. Any suspected toxicity or dangerous drug interaction requires urgent professional assessment.