Herb Profile
Longan
Dimocarpus longan
Longan (Dimocarpus longan) carries a Grade C rating — limited evidence.
Last reviewed: •3 sources citedReport a correctionProfile-wide ·C Limited
Use extra caution — CNS active potential; avoid stacking with sedatives, alcohol, sleep aids, antidepressants, or other psychoactive supplements without clinician review. Details
- Evidence
- Limited Evidence
- Typical onset
- Varies by prep
- Safety rating
- High caution
- Best for
- Sleep, Stress
- Avoid / review if
- Pregnancy/Breastfeeding Without Clinician Supervision, Known Allergy To The Plant/Family, Potential Interaction Concern With Sedatives/CNS Depressants
Safety
Safety & Cautions
CNS active potential; avoid stacking with sedatives, alcohol, sleep aids, antidepressants, or other psychoactive supplements without clinician review. Avoid pregnancy/breastfeeding use unless supervised.
High caution
Caution level: High. Multiple caution categories apply, or the record uses avoid/contraindication language.
- Interaction-AwareMedication or interaction context is explicitly noted.
- Pregnancy/Breastfeeding CautionPregnancy or breastfeeding caution language is present.
Detailed safety fields
Pregnancy, breastfeeding, and contraindications
- Pregnancy/Breastfeeding Without Clinician Supervision
- Known Allergy To The Plant/Family
- Potential Interaction Concern With Sedatives/CNS Depressants
- Use Clinician Review For High Dose Extracts Or Chronic Use.
Safety classifications
- Interaction-Aware: Medication or interaction context is explicitly noted.
- Pregnancy/Breastfeeding Caution: Pregnancy or breastfeeding caution language is present.
Full safety note
- CNS active potential; avoid stacking with sedatives, alcohol, sleep aids, antidepressants, or other psychoactive supplements without clinician review. Avoid pregnancy/breastfeeding use unless supervised.
Safety labels
- Interaction-Aware
- Pregnancy/Breastfeeding Caution
Evidence-based safety
Caution when combined
Severity and certainty are shown separately. A high-priority caution can still be theoretical: these pairings are screened from shared contraindication mechanisms and are not automatically documented clinical interactions. Provenance identifies the source fields that produced each flag; it does not upgrade the certainty of the pairwise claim.
Moderate Caution
68 flagged pairingsSedation / CNS depression
Moderate Caution
68 flagged pairingsSedation / CNS depression
Representative pairings are shown below. Large mechanism groups are intentionally summarized to keep profiles focused and crawl-efficient.
Sedation / CNS depressionCertainty: Theoretical
Data provenance recorded for 68 of 68 pairings in this mechanism group.
- American Yellow Lotus — Theoretical interaction certainty
- Artemisia Absinthium — Theoretical interaction certainty
- Ashwagandha (Withania somnifera) — Theoretical interaction certainty
- Bacopa — Theoretical interaction certainty
- Black Seed — Theoretical interaction certainty
- Black Tea — Theoretical interaction certainty
- Blue Lotus — Theoretical interaction certainty
- Calamus — Theoretical interaction certainty
- Catuba — Theoretical interaction certainty
- Celastrus Paniculatus — Theoretical interaction certainty
- Chamomile — Theoretical interaction certainty
- Chinese Skullcap — Theoretical interaction certainty
+56 more pairings share this mechanism. Use the Safety Checker to review a specific combination.
Evidence
Evidence Summary
Evidence lens
Read as directional context, not settled clinical proof.
LimitedLimited Evidence
Human clinical evidence: Not the primary signal
Mechanistic / preclinical: Mechanism mapped — Oxidative Stress Modulation · Stress Response Modulation
Research maturity: Theoretical / mechanistic research — Mechanistic or unresolved evidence is kept separate from established human outcomes.
Safety boundary: Safety note available — CNS active potential; avoid stacking with sedatives, alcohol, sleep aids, antidepressants, or other psychoactive supplements without clinician review.
This profile cites 3 human studies.
Study design details
Evidence Grade
Grade C: Limited Evidence
Evaluation of methodological rigor, population reach, and evidence alignment.
- Design Match
- Narrative review
- Risk of Bias
- High
- Consistency
- Not assessed
Strongest recorded design is a narrative review, drawn from 3 recorded studies, none of which measured an outcome in people.
How evidence grades work
Each grade reflects the strength and consistency of published human evidence — not marketing claims. Grades are based on study count, design quality, effect size, consistency, and recency.
- Strong
- Multiple RCTs, consistent direction, adequate effect size
- Moderate
- Some RCTs or consistent observational data in humans
- Preliminary / Mixed
- Animal or in-vitro only, or conflicting human data
- Traditional / Theoretical
- Traditional use only; no controlled human trials
Clinical Study Summaries (5)0 human evidence sources · 0 human trials · Participant totals not consistently reported · Consistency not yet classifiable
Filter by study class
Showing 5 of 5 studies.
What the evidence actually shows
This table contains 5 structured sources, including 0 human evidence sources; 0 are human trials.
| Study | Design | N | Dose | Duration | Population | Outcome | Result & magnitude | Source |
|---|---|---|---|---|---|---|---|---|
Recent chemical synthesis of plant polysaccharides Wang X et al. · Curr Opin Chem Biol · 2023 Background | Narrative review Summarizes selected literature without the full prespecified search and selection methods of a systematic review. | — | — | — | — | — | — | PubMed → |
Zhu XR et al. · J Zhejiang Univ Sci B · 2019 Background | Narrative review Summarizes selected literature without the full prespecified search and selection methods of a systematic review. | — | — | — | — | — | — | PubMed → |
Background | Narrative review Summarizes selected literature without the full prespecified search and selection methods of a systematic review. | — | — | — | — | — | A 2025 comprehensive review defines Longan Arillus as the fruit aril and catalogues 378 identified compounds, with polysaccharides and polyphenols emphasized. The review also concludes that in-vivo and clinical studies remain relatively limited, so broad pharmacologic activity should not be presented as established human benefit. | PubMed → |
Background | In-vitro research Studies cells, tissues, or biochemical systems outside a living person. It is preclinical evidence, not proof of a human outcome. | — | — | — | — | — | A 2025 study reported sleep-related enzyme/pathway effects in cell models using longan flower ethanol extract. It is not human sleep evidence and is plant-part specific, so it should be labeled mechanistic/preclinical rather than a clinical benefit. | PubMed → |
Chen Y et al. · Plant Physiol · 2023 Background | Other / unclear The study design is not yet classified clearly enough to infer its place in the evidence hierarchy. | — | — | — | — | — | — | PubMed → |
Dosing & Timing
- No standardized dose
- Preparation specific; use standardized product label for Fruit/berry preparations are commonly used as foods and require source backed dosage review before therapeutic claims.
How Longan works
Simplified mechanism pathway based on preclinical and pharmacological evidence. Does not confirm clinical efficacy.
Mechanism Pathway — How Longan Works
CompoundTarget / ReceptorMechanismEffect / Outcome
Mechanisms & biological pathways (preclinical)
- Oxidative Stress Modulation
- Stress Response Modulation
Active Compounds
Key constituents studied in Longan, with full pharmacology and safety profiles.
Compare related active botanicals
Explore botanicals with similar chemistry, effects, or safety considerations in the Botanical Activity Atlas.
Compare & Sourcing
Compare side-by-side tradeoffs or verify active marker guidelines.
Safety first · Harm reduction
This information is educational and not medical advice. Start low, avoid risky combinations, and consult a licensed clinician before making health decisions—especially if you use medications, have diagnosed conditions, or are pregnant/breastfeeding.
Learn how we evaluate confidence, safety, and intensity on the methodology page.
Founder & Head Researcher · Oak Ridge, TN · Last reviewed August 2026
Editorial Review
Checked against primary sources, cited evidence, and contraindication language before publication. Evidence claims, safety language, and affiliate modules are reviewed independently. Not personal medical advice.
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