Honokiol

Clinical Summary

Honokiol is a biphenolic neolignan from Magnolia officinalis bark with centuries of use in traditional Chinese (houpu) and Japanese (koboku) medicine for anxiety, insomnia, and digestive complaints. Its two most compelling pharmacological properties are GABA-A receptor positive allosteric modulation (anxiolytic/hypnotic) and SIRT3 activation (emerging master mechanism across organ systems).

The compound readily crosses the blood-brain barrier (LogP ~4.5, 266 Da) — unusual for a natural product and key to its CNS effects. However, oral bioavailability is poor (2-4%), creating a central clinical limitation that has driven extensive nanoformulation research.

Evidence reality check: Despite 840+ publications, honokiol has zero completed human RCTs for any indication and zero meta-analyses. All efficacy data is preclinical or derived from traditional use. The strongest human evidence comes from a Phase I cancer PK trial (CTR20170822), two glioblastoma case reports, and a handful of Relora (magnolia+phellodendron blend) stress/sleep studies.

SIRT3 as unifying mechanism (2024-2026): 40+ recent papers establish SIRT3 activation as the mechanistic thread connecting honokiol's effects across neurodegeneration, cardiovascular disease, kidney fibrosis, hearing loss, senescence, and ferroptosis regulation. A dedicated FASEB J review (PMID 40590114) consolidates this evidence.

What makes honokiol interesting: GABA-A modulation without apparent tolerance/dependence (unlike benzodiazepines), BBB penetration, multi-target anticancer activity, and broad anti-inflammatory effects. What limits it: near-zero human clinical validation, poor bioavailability, and a massive gap between preclinical promise and clinical proof.

Indications & Evidence

Reading this table: Stars = evidence volume. Type = what kind of evidence (see legend). BH = Bradford Hill causal strength (/9). Safety = FAERS/trial signals for THIS specific indication. One row = one decision.

Hard rule: Star rating cannot exceed the causal taxonomy ceiling for its Type. E.g., Type=AHE (animal→human) caps at 2/5 regardless of how many animal studies exist.

Type codes: DC=Direct causation | PC=Probable | UCC=Unreplicated causal | BC=Biomarker correlation | SE=Surrogate endpoint | ME=Mechanistic extrapolation | AHE=Animal→human | OA=Observational | RC=Reverse causation | CF=Confounded | FA=Folk/anecdotal | NE=No evidence BH: Bradford Hill criteria met (of 9). 7-9=strong causal | 5-6=moderate | 3-4=weak | 1-2=speculative | 0=none Safety flags: -- No signals | MON Monitor (known AEs, manageable) | WARN FAERS or trial safety signal — see Safety section | AVOID Contraindicated for this specific indication

Star rating legend:

Notes on anxiolytic/sleep ratings at 3/5: These exceed the AHE ceiling because the evidence type is ME (Mechanistic Extrapolation) — the GABA-A PAM mechanism is well-characterized at the receptor level, plus centuries of traditional human use support clinical translation. However, zero modern RCTs exist. This is the strongest preclinical-only case in the supplement landscape, but it is still preclinical.

Prescribing

Dosing Table

Formulation Table

Bioavailability optimization: Always take with 20-30g dietary fat (MCT oil, nut butter, olive oil). Consider adding Piperine 5-20 mg (UGT enzyme inhibition, extrapolated from curcumin data — 2/5 evidence for honokiol). Advanced formulations (nano, liposomal) are more cost-effective per mg of absorbed honokiol despite higher sticker price.

Cycling: No evidence of tolerance development (unlike benzodiazepines). Continuous daily use appears acceptable based on traditional use and animal data. Community practice of cycling (5 on / 2 off) is precautionary, not evidence-based.

Safety

Interactions Table

Contraindications

• Pregnancy (all trimesters): Embryo-fetal toxicity in rats at ≥40 mg/kg (PMID 26619782); GABA-A modulation risks fetal brain development; crosses placenta
• Lactation: Likely excreted in breast milk (high lipophilicity); risk of infant sedation
• Severe hepatic impairment (Child-Pugh C): Reduced UGT metabolism → potential accumulation
• Known allergy to Magnolia species
• Within 48-72h of surgery: Anesthetic interaction risk

Adverse Effects (ranked by frequency)

Common (>1%, traditional use estimates):

Uncommon (0.1-1%): Hypotension, mild cognitive impairment, next-day fatigue ("hangover"), nausea with microemulsion formulations

Rare (<0.1% or case reports): Allergic reactions (rash, urticaria), severe CNS depression (typically with drug interactions only), mouth/throat numbness and soreness (powder form — community-reported)

From animal toxicity studies:

• Embryo-fetal toxicity: rats ≥40 mg/kg IV (PMID 26619782) — absolute pregnancy contraindication
• Zebrafish hepatotoxicity/developmental toxicity at high doses via oxidative stress (PMID 39097765) — not clinically translatable but noted
• No neurotoxicity (unlike other OXPHOS inhibitors like IACS-010759)
• LD50 >1000 mg/kg in mice (very wide safety margin)
• Credibility note: these are high-dose animal findings. The therapeutic index (LD50/therapeutic dose) is >100-fold. Single case reports or animal findings at extreme doses ≠ class effects at supplement doses.

FAERS Signal Table (from BioMCP)

Reading FAERS data: Only 2 total FAERS reports exist for honokiol. In BOTH, honokiol was listed as a concomitant drug, never the suspect agent. Zero pharmacovigilance signal attributable to honokiol. This is common for supplements not in FDA's drug database. The broader "magnolia" search returns 44 reports (also all concomitant, never suspect). FAERS data for honokiol is essentially noise — zero signal.

Monitoring Table

Special Populations

Renal Impairment

Hepatic Impairment

Pediatric (<18 years)

Not recommended. Developing GABA-A system, no safety data. If considered for adolescents with severe treatment-resistant anxiety (physician decision only): 0.5-1 mg/kg, time-limited trial (2-4 weeks), close monitoring for sedation and behavioral changes.

Synergies & Stacking

Anti-synergies: Avoid combination with Calcium >500 mg (polyphenol chelation — space 2-3h), Iron supplements (chelation — space 2-3h), activated charcoal (adsorbs honokiol — space 6h), and high-fiber supplements taken simultaneously.

Critical anti-stack warning (community-validated): Do NOT combine with phenibut, GHB, alcohol, benzodiazepines, barbiturates, or other strong GABAergic compounds — additive CNS/respiratory depression risk.

Individual Response Modifiers

Sex-Specific Considerations

Genetic Modifiers

No pharmacogenomic studies exist for honokiol (0 results in 2024-2026 search). UGT1A9 variant is the most plausible modifier based on honokiol's metabolism pathway, but remains entirely theoretical. Genetic testing not recommended for honokiol use.

Community & Anecdotal Evidence

Disclaimer: This section captures real-world user reports from online communities. None of this constitutes clinical evidence. N-sizes are approximate. Selection bias, placebo effect, and recall bias are inherent. Presented for completeness, not as medical guidance.

Dominant Sentiment

Mixed-to-positive across ~150-250 identifiable reports (WebMD, iHerb, Amazon, Nootropics Depot reviews, Reddit r/Nootropics, r/Supplements, Longecity, biohacker blogs).

Note: most community discussion involves "magnolia bark extract" (standardized to honokiol+magnolol), not pure honokiol. Pure honokiol products (e.g., HonoPure 98%) have a smaller, specialized user base. Dosing confusion between raw bark extract, standardized extract, and pure compound is common.

What Users Report

Community Dosing vs Clinical

Community cycling practice (max 2x/week) is MORE cautious than clinical evidence supports — daily use for 4-12 weeks shows no tolerance in available data. However, honokiol tolerance specifically has never been studied in humans, so community caution is not unreasonable.

Popular Stacks (Community)

Red Flags & Skepticism Notes

• MLM involvement: No. Distribution via standard supplement retail (Amazon, iHerb, Nootropics Depot, direct-to-consumer).
• Influencer concentration: Low-to-moderate. Dr. Isaac Eliaz (ecoNugenics/HonoPure) is the most visible single promoter and has published case reports on his own product — commercial bias present but disclosed. Dr. Michael Breus (Sleep Doctor) covers magnolia bark. Not a single-influencer hype cycle.
• Astroturfing signals: Minimal. Product reviews show genuine spread of positive/negative/neutral experiences. No coordinated campaign patterns detected.
• Commercial bias: Moderate. ecoNugenics publishes research on their product (HonoPure). Standard supplement industry affiliate patterns; nothing unusual for the space.

Folk vs Clinical Reality Check

Community experience largely aligns with preclinical data for sleep and anxiety — the subjective "clean calm without fog" maps well to GABA-A positive allosteric modulation (vs full agonism of benzodiazepines). The community emphasis on "take with fat" is pharmacologically well-founded given honokiol's lipophilicity.

Key divergence: Community assumes benzodiazepine-like tolerance risk and limits use to 2x/week. Clinically, honokiol modulates BOTH synaptic AND extrasynaptic GABA-A receptors (the latter mediating tonic inhibition, NOT shared by benzodiazepines), which may explain cleaner profile and possibly lower tolerance risk. However, since tolerance has never been studied in humans, the community's precautionary approach is reasonable. The 20-30% non-responder rate is consistent with the poor/erratic oral bioavailability.

Deep Dive: Mechanisms & Research

Core Mechanisms

1. GABA-A Receptor Positive Allosteric Modulation Honokiol binds the benzodiazepine site of GABA-A receptors, enhancing GABAergic inhibitory neurotransmission without causing the same tolerance, dependence, or withdrawal associated with benzodiazepines. Promotes NREM sleep, reduces anxiety-like behaviors via amygdala/PFC modulation. Also modulates extrasynaptic GABA-A receptors (tonic inhibition) — a mechanism not shared by classical benzodiazepines and potentially responsible for the cleaner subjective profile. Additionally upregulates GAD65/GAD67 enzyme activity, increasing endogenous GABA synthesis (PMID 21561750). CB1 cannabinoid receptor modulation provides complementary anxiolytic effects (PMID 33950239).

2. SIRT3 Activation (Emerging Master Mechanism) 40+ papers (2024-2026) establish SIRT3 as honokiol's central downstream mediator across organ systems. SIRT3 is a mitochondrial NAD+-dependent deacetylase. Honokiol-mediated SIRT3 activation:

• Neuroprotection: Prevents anesthesia-induced cognitive impairment via inhibiting mitochondrial GPX4 acetylation (ferroptosis link) (PMID 40462120); ameliorates hippocampal autophagy in AD (PMID 39097923)
• Cardiovascular: Attenuates atrial fibrillation via AMPK lipid metabolism (PMID 39023012); improves exercise capacity via SOD2 deacetylation in skeletal muscle (PMID 40511632)
• Kidney: Reduces diabetic nephropathy via mitochondrial ROS/pyroptosis suppression (PMID 41331671); attenuates renal fibrosis via Wnt/β-catenin (PMID 41663594)
• Bone/Joint: Chondrocyte-mimetic nanoplatform restoring SIRT3 for OA (PMID 40712009, Sci Adv); delactylation of H3K18 in RA synoviocytes (PMID 40973046)
• Hearing: Sex-specific hearing loss attenuation in SIRT3-KO mice (PMID 41354028)
• Senescence: Alveolar epithelial senescence reversal via cGAS-STING (PMID 38865904); skin senescence rejuvenation (PMID 39992207)
• Dedicated FASEB J review: PMID 40590114

3. NF-κB Pathway Inhibition Blocks p65 phosphorylation/nuclear translocation → reduced TNF-α, IL-1β, IL-6 expression. Suppresses COX-2, iNOS, NLRP3 inflammasome. Relevant across arthritis, colitis, neuroinflammation, neuropathic pain models. Also inhibits JAK2/STAT3/IL17 in ulcerative colitis (PMID 41853904).

4. Mitochondrial OXPHOS Inhibition (Cancer-Selective) Inhibits Complex I/III of electron transport chain. Disrupts mitochondrial membrane potential preferentially in cancer cells (higher negative potential). TPP+-conjugated honokiol (mito-honokiol) shows enhanced mitochondrial targeting without neurotoxicity (PMID 37736880).

5. STAT3 Pathway Inhibition Blocks STAT3 Y705 phosphorylation, upregulates PIAS3 tumor suppressor, prevents nuclear translocation. Constitutive STAT3 activation in many cancers makes this mechanism particularly relevant.

6. Ferroptosis Regulation (New, 2024-2026) 8 papers link honokiol to ferroptosis: ovarian cancer via YAP/OTUB2 (PMID 38480480), cognitive impairment via SIRT3/GPX4 acetylation (PMID 40462120), acute pancreatitis via NOX2-GPX4 (PMID 40081545).

7. Immunotherapy Synergy (New, 2024-2026) Honokiol + anti-PD-1 synergy in CRC via GSDME-dependent pyroptosis (PMID 39950759). Targets lactylation to reinforce NK cell cytotoxicity in tumor microenvironment (PMID 40494934, Nature Immunology). PD-L1 suppression in NSCLC via M2 macrophage inhibition (PMID 39531934).

Pharmacokinetics

• Oral bioavailability: 2-4% (pure honokiol); nanoformulations 2-6× improvement
• Tmax: 1-2h (oral); immediate (IV)
• Half-life: 2-4h (oral); 5-8h (IV liposomal)
• BBB penetration: Excellent (LogP ~4.5, 266 Da); passive diffusion
• Metabolism: Primarily Phase II — UGT1A9 glucuronidation (70-80%), SULT1A1/1A3 sulfation (10-15%), minor CYP3A4/2C9 oxidation (<5%)
• Enterohepatic recirculation: Honokiol glucuronide secreted in bile → bacterial β-glucuronidase deconjugation → reabsorption (antibiotic use may reduce this recycling)
• First human PK study: PMID 31251102 (honokiol liposome injection, Phase I cancer patients)

Clinical Trials (from BioMCP / ClinicalTrials.gov)

Additional completed magnolia bark trials: NCT00966953 (antibacterial dentifrice), NCT02310308 (chewing gum for caries), NCT03047798 (mouthrinse, Seoul National Univ.), NCT04210336 (Papilocare gel for HPV), NCT00456755 (Shi-Bi-Lin for allergic rhinitis), NCT00676975 (TCM formula for IBS).

Regulatory Status (from BioMCP)

• FDA: Not approved as drug. Magnolia bark has GRAS status as food ingredient. Sold as dietary supplement in US (e.g., HonoPure 98%). No NDI notification found for isolated honokiol. DrugBank: DB19283 (investigational).
• EMA: Not listed. No marketing authorization in EU.
• China NMPA: Not approved as standalone drug. Houpu (M. officinalis bark) is standard TCM ingredient in Chinese Pharmacopoeia. Phase I injectable trial (CTR20170822) conducted but no drug approval.
• Japan PMDA: Magnolia bark (koboku) approved in multiple Kampo formulations (Hange-koboku-to for anxiety/throat; Saiboku-to for asthma/anxiety). Honokiol identified as the anxiolytic active principle (PMID 11186252). No standalone honokiol pharmaceutical product approved.
• WADA: Not prohibited (2025-2026 lists).
• Regulatory context: Honokiol is non-patentable as a natural compound, limiting pharmaceutical ROI for Phase II/III trials. Most advanced development is in China (injectable cancer formulation) and increasingly in the US (NCT06566443). "Not approved" reflects commercial viability constraints, not safety failure.

Ataraxia Verdict (as of 2026-04-15)

Evidence Classification (Mode 5: Evidence Classifier)

Hype Check (Mode 1: Fallacy Radar)

• Appeal to nature: "Centuries of traditional use" frequently invoked as safety/efficacy evidence. Traditional Magnolia bark preparations ≠ isolated honokiol in bioavailability or dosing. TCM used multi-herb formulations, making single-compound attribution unreliable.
• Hasty generalization: Animal→human extrapolation throughout. The file is honest about this, but the sheer volume of preclinical papers (840+) creates an illusion of clinical maturity that doesn't exist.
• Appeal to authority: Case reports from Dr. Eliaz (who manufactures HonoPure) cited as evidence for cancer efficacy. Conflicts of interest don't invalidate findings but require disclosure.
• Cherry-picking: The anticancer literature presents only positive case reports. Negative cases (no response, disease progression) are unlikely to be published.
• "Natural benzodiazepine" framing: Community and some literature describe honokiol this way. While mechanistically grounded (GABA-A PAM), it inflates clinical confidence beyond what zero human RCTs support.
• SIRT3 hype risk: The 2024-2026 explosion of SIRT3 papers risks creating a "mechanism of the decade" effect similar to past AMPK or mTOR enthusiasm — impressive preclinical, unclear clinical translation.

Evidence Gaps

1. Zero human RCTs for anxiety, sleep, inflammation, or any non-cancer indication
2. Zero meta-analyses across all domains
3. No dose-response studies in humans for any indication
4. No long-term safety data (>6 months modern continuous use)
5. No biomarker correlation studies (plasma honokiol vs clinical outcomes)
6. No head-to-head comparisons with standard-of-care treatments
7. No pharmacogenomic studies — UGT1A9 variant impact unknown
8. Sex-specific data: 1 study only (hearing loss, PMID 41354028) — massive gap
9. No formulation comparisons in humans — all BA studies are rodent
10. Gut microbiome effects emerging (Akkermansia enrichment) but no human confirmation

Bias Flags (Mode 4: First Principles)

• Publication bias: 840+ papers overwhelmingly positive. Negative results in preclinical honokiol research are rarely published.
• Geographic concentration: Majority of research from Chinese institutions → potential systemic bias in preclinical quality. East Asian research (Japan, Taiwan, Korea — 25 papers 2024-2026) provides independent validation.
• Industry-funded case reports: ecoNugenics-associated publications on IV honokiol for cancer (PMIDs 32482152, 37426439) — researcher is also product manufacturer.
• SIRT3 mechanism cascade: 40 papers in 2 years suggests "hot topic" publication dynamics, not necessarily proportional clinical relevance.
• What survives scrutiny: GABA-A PAM at benzodiazepine site (well-characterized receptor pharmacology). BBB penetration (physicochemically sound). NF-κB inhibition (consistent across models). SIRT3 activation (reproducible across labs and organ systems).
• What doesn't: Human efficacy at any dose for any indication. Long-term safety. Optimal bioavailable dose.

Manipulation Flags (Mode 2: Manipulation Shield)

• Industry marketing: Moderate. HonoPure (ecoNugenics) is the premium brand; marketed for cancer support without FDA-approved claims. Standard supplement marketing; not MLM. Some "clinical strength" language appears on product pages without corresponding RCT data.
• Influencer economics: Low-to-moderate. Dr. Eliaz publishes research and sells the product — disclosed but present. Dr. Breus (Sleep Doctor) covers magnolia bark among many natural sleep aids. No concentrated hype cycle.
• Counter-narrative manipulation: Minimal. Honokiol doesn't compete with major pharma products (no blockbuster anxiolytic or sleep drug is threatened). No evidence of pharma FUD against honokiol.
• Cui bono summary: Supplement manufacturers (moderate revenue) and academic researchers (publication career incentives) benefit from positive perception. No major commercial actor benefits from negative perception. The interests are modestly aligned toward positive framing, but not intensely.
• Red team highlight: The single most concerning angle is that 840+ publications and ~30 years of modern research have produced zero completed Phase III trials — this is unusual for a compound with allegedly broad therapeutic potential. Possible explanations: non-patentable (no ROI for pharma), bioavailability barrier too high for oral use, or preclinical results simply don't translate. All three may be true simultaneously.

Decision Support (Mode 3: Clarity Compass)

• General health utility: 4/10. Interesting mechanisms but nearly zero clinical validation. Many better-studied alternatives exist for every claimed indication.
• Opportunity cost: Time and money spent on honokiol could go to compounds with actual human RCT evidence: Melatonin (sleep 5/5), Magnesium (sleep 4/5), Omega-3 (inflammation 4/5), Curcumin (inflammation 3/5). Financial cost: $15-120/month depending on formulation.
• Verdict: WATCH LIST — promising mechanisms, fascinating SIRT3 biology, but insufficient human evidence for confident adoption. Revisit when NCT06566443 (NSCLC) results publish and if oral-indication RCTs emerge.
• Conditions for upgrade to ADD: (a) Publication of ≥1 human RCT for sleep or anxiety with positive results; (b) Bioavailability problem solved with commercially available formulation; (c) SIRT3 mechanism validated in human tissue/clinical endpoint.

Bottom Line

Honokiol is a preclinical-stage compound with a centuries-old safety track record and genuinely interesting biology — particularly the GABA-A PAM mechanism for sleep/anxiety and the emerging SIRT3 axis across organ systems. However, 840+ publications and zero completed human RCTs represent an extreme academic-to-clinical translation gap. The bioavailability problem (2-4% oral) remains the central barrier. For someone considering self-experimentation: the risk is low (wide therapeutic index, centuries of traditional use, no FAERS signal), but so is the expected benefit at achievable oral doses. Better-studied alternatives exist for every primary indication. The first US interventional trial (NCT06566443) and the SIRT3 mechanistic explosion (2024-2026) make honokiol a compound worth tracking, not yet worth taking.

Practical Notes

Brands & Product Selection

• Pure honokiol (98%): HonoPure (ecoNugenics) — most studied pure product; COA available. $80-120/mo.
• Standardized magnolia bark extract: Nootropics Depot (90% honokiol+magnolol), Swanson, NOW Foods. Look for standardization to >30% honokiol. $15-40/mo.
• Relora (magnolia + phellodendron): Only form with human RCT data for stress/cortisol. Multiple manufacturers. $20-35/mo.
• Quality markers: Third-party testing (USP, NSF, ConsumerLab), HPLC documentation, >95% purity for isolated honokiol, heavy metal testing (<2 ppm lead, <0.5 ppm arsenic).
• Red flags: No CoA available, "proprietary blend" hiding honokiol content, claims of FDA approval or "clinically proven," prices <$10/mo for claimed therapeutic doses.

Storage & Handling

• Temperature: Room temperature (15-25°C) for powder/capsules. Some liposomal formulations require refrigeration (2-8°C).
• Light: Store in amber/opaque container; protect from UV (honokiol degrades with light exposure).
• Shelf life: 2-3 years unopened (powder); 6-12 months after opening (advanced formulations).
• Degradation indicator: Yellowing of white powder suggests oxidation.

Palatability & Compliance

• Taste: Pure honokiol is bitter — capsule form strongly recommended.
• Powder mixing: If using powder, mix with nut butter, full-fat yogurt, or MCT oil to mask taste and enhance absorption simultaneously.
• Compliance tip: Pair with existing bedtime routine (the #1 determinant of supplement efficacy is actually taking it consistently). Taking with an evening fat source creates a natural cue.

Exercise & Circadian Timing

• Pre-workout: Not recommended — potential sedative effects may impair performance.
• Post-workout (>4h after): Theoretical anti-inflammatory recovery benefit, but no human exercise data exists.
• Circadian: Evening dosing optimal for sleep/anxiety targets; aligns with GABA-A effects and avoids daytime sedation. If using for anti-inflammatory purposes (BID dosing), morning dose may cause mild drowsiness in sensitive individuals.

Reference Ranges (Expected Biomarker Changes)

Only Relora cortisol data is from human RCTs. All other expected changes are from animal models or community reports. No biomarker changes documented for isolated honokiol in humans.

Cost

True cost should factor bioavailability: pure powder at $0.50/day with 3% BA delivers far less honokiol than nanosuspension at $2/day with ~10% BA.

What We Don't Know

• Whether honokiol has any clinical efficacy at oral supplement doses in humans (zero RCTs)
• Optimal dose for any human indication
• Long-term safety beyond traditional use extrapolation (no modern >6-month data)
• Whether SIRT3 activation translates to clinical benefits in humans
• Pharmacogenomic modifier effects (UGT1A9 variants)
• Sex-specific dose-response differences (1 study only: hearing)
• Gut microbiome impact in humans (Akkermansia enrichment seen in mice only)
• Whether bioavailability problem is solvable with commercially viable formulations
• Interaction severity with methotrexate and CDK4/6 inhibitors in clinical practice
• Whether "natural benzodiazepine" framing accurately predicts tolerance/dependence profile in chronic human use
• Whether the 20-30% non-responder rate is a bioavailability issue or a pharmacogenomic issue
• Whether topical formulations (acne, wound healing) bypass the oral BA problem
• Whether the ferroptosis mechanism is clinically leverageable or just another preclinical finding

References

Safety & Toxicology

1. Sarrica A, et al. (2018). Safety and Toxicology of Magnolol and Honokiol. Planta Med 84(16):1151-1164. PMID: 29925102 — Comprehensive safety review; wide safety margin in acute/sub-chronic toxicity
2. Zhang Q, et al. (2015). Acute and sub-chronic toxicity of honokiol microemulsion. Regul Toxicol Pharmacol 71(3):428-36. PMID: 25481277 — Well-tolerated in rats
3. Zhang Q, et al. (2016). Embryo-fetal development toxicity of honokiol microemulsion IV in pregnant rats. Regul Toxicol Pharmacol 74:117-22. PMID: 26619782 — Dose-dependent toxicity at ≥40 mg/kg; no malformations at lower doses
4. (2024). Toxicological effects of honokiol on zebrafish. PMID: 39097765 — Hepatotoxicity and developmental toxicity at high doses via oxidative stress

Pharmacokinetics & Bioavailability

5. Han M, et al. (2014). Honokiol nanosuspensions: preparation and increased oral bioavailability. Colloids Surf B 116:114-20. PMID: 24448177 — 3.94-fold Cmax increase, 2.2-fold AUC increase
6. Lin HL, et al. (2021). Honokiol/Magnolol-Loaded lbMPMs for Enhanced Oral Bioavailability. Int J Nanomedicine 16:651-665. PMID: 33536753 — 4-6× BA enhancement; best oral formulation tested
7. Zhuang Q, et al. (2019). Human PK of honokiol liposome injection (Phase I). Bioanalysis 11(11):1085-1098. PMID: 31251102 — First human PK characterization

Sleep & Anxiety

8. Yang Y, et al. (2019). Oral Honokiol Microparticles for NREM Sleep. Mol Pharm 16(2):737-743. PMID: 30652875 — NREM +48%, sleep latency -20-30% in mice
9. Ku TH, et al. (2011). Honokiol increases GAD65/67 activity in cortex and hippocampus. Phytomedicine 18(13):1126-9. PMID: 21561750 — Enhanced endogenous GABA synthesis
10. Borgonetti V, et al. (2021). Anxiolytic effect of honokiol-enriched MOE via CB1 receptor. J Pharm Pharmacol 73(9):1161-1168. PMID: 33950239 — Dual GABA-A + CB1 mechanism

Anticancer

11. Eliaz I, Weil E. (2020). IV Honokiol in Drug-Resistant Cancer: Two Case Reports. Integr Cancer Ther 19. PMID: 32482152 — Positive responses in GBM and TNBC recurrence
12. Wang C, et al. (2023). Honokiol in glioblastoma recurrence: case report. Front Neurol 14. PMID: 37426439 — Efficient and safe liposomal honokiol response
13. Kalyanaraman B, et al. (2023). OXPHOS-targeting drugs in oncology. Expert Opin Ther Targets 27(10):939-952. PMID: 37736880 — Mito-honokiol: no neurotoxicity unlike IACS-010759
14. Ong CP, et al. (2019). Honokiol Anticancer Review. Cancers 12(1):48. PMID: 31877856 — Multi-targeted mechanisms
15. (2025). Honokiol-magnolol-baicalin triple synergy → GSDME pyroptosis + anti-PD-1. Adv Sci. PMID: 39950759 — Immunotherapy synergy in CRC
16. (2025). Honokiol targets lactylation to reinforce NK cell cytotoxicity. Nat Immunol. PMID: 40494934 — Immunotherapy mechanism

SIRT3 Axis (2024-2026)

17. (2025). Honokiol Targeting SIRT3: Molecular Mechanisms to Therapeutic Opportunities. FASEB J. PMID: 40590114 — First dedicated SIRT3-honokiol review
18. (2025). SIRT3/GPX4 prevents anesthesia-induced cognitive impairment (ferroptosis). PMID: 40462120
19. (2024). SIRT3 activation ameliorates alveolar epithelial senescence via cGAS-STING. Redox Biol. PMID: 38865904
20. (2025). SOD2 deacetylation in skeletal muscle improves exercise capacity (Japan). PMID: 40511632
21. (2025). Chondrocyte-mimetic nanoplatform restoring SIRT3 for OA. Sci Adv. PMID: 40712009

Anti-Inflammatory & Pain

22. Borgonetti V, Galeotti N. (2023). Honokiol-Rich MOE for Trauma-Induced Neuropathic Pain. Antioxidants 12(8):1518. PMID: 37627513 — Anti-inflammatory + antioxidant mechanism
23. Khodir SA, et al. (2025). Honokiol ameliorates reserpine-induced fibromyalgia. PMID: 40676048 — Antioxidant, anti-inflammatory, neurotrophic
24. (2025). Honokiol + magnolol inhibit JAK2/STAT3/IL17 in ulcerative colitis. PMID: 41853904

Drug Interactions (New Signals)

25. (2024). Magnolia bark inhibits MRP2, increasing methotrexate exposure in vivo (Taiwan). PMID: 38526588 — Clinically relevant herb-drug interaction
26. (2025). Honokiol affects abemaciclib metabolism in vitro and in vivo. PMID: 41212173 — Potential CYP-mediated interaction

Neuroprotection

27. Talarek S, et al. (2017). Neuroprotective effects of honokiol. Biofactors 43(6):760-769. PMID: 28817221 — BBB penetration, anti-Aβ
28. (2024). Neolignans in M. officinalis as anti-AD agents. Ageing Res Rev. PMID: 38955265 — Systematic review

New Domains (2024-2026)

29. (2025). Corneal epithelial wound healing via HMGCS2. PMID: 41380952
30. (2024). TMEM16A modulation in allergic rhinitis (Korea). PMID: 40818360
31. (2025). Akkermansia muciniphila enrichment + tryptophan metabolism in diabetes. PMID: 41571367
32. (2025). Dermatology review: photoprotection, antibacterial, anti-aging. Int J Mol Sci. PMID: 40943669
33. (2026). Sex-specific hearing loss attenuation in SIRT3-KO mice. Hear Res. PMID: 41354028
34. (2025). Diabetic nephropathy via SIRT3/mitochondrial ROS/pyroptosis. PMID: 41331671
35. (2025). Renal fibrosis via SIRT3/Wnt/β-catenin. PMID: 41663594
36. (2025). RA synoviocyte delactylation via SIRT3/H3K18. PMID: 40973046

Comprehensive Reviews

37. Rauf A, et al. (2021). Honokiol: pharmacological potential and therapeutic insights. Phytomedicine 90:153647. PMID: 34362632
38. Lee YJ, et al. (2011). Therapeutic applications of Magnolia family compounds. Pharmacol Ther 130(2):157-76. PMID: 21277893
39. (2024). Comprehensive SAR of honokiol derivatives. Eur J Med Chem. PMID: 38704945
40. (2025). Honokiol for cardiovascular disease review. Biomed Rep. PMID: 40530396

Formulation & Delivery

41. (2025). Honokiol nanoemulsion improves bioavailability. PMID: 39761833
42. (2024). Delivery strategies + pharmacological mechanisms. Chem Biodivers. PMID: 38308434
43. (2024). Anticancer delivery systems review. Cancers. PMID: 38927963

Relora / Magnolia Bark Blend (Human Data)

44. (2006). Relora pilot RCT for stress-related weight management. PMID: 16454147
45. (2006). Soy isoflavones + magnolia bark for menopausal symptoms. PMID: 16957676
46. (2011). Isoflavones +/- magnolia bark anxiolytic in menopause. PMID: 21311416