Herb Profile
Guayusa
Ilex guayusa
Guayusa (Ilex guayusa) carries a Grade C rating — limited evidence.
Last reviewed: •3 sources citedReport a correctionProfile-wide ·C Limited
Use extra caution — Caffeine containing herb; may worsen insomnia, anxiety, palpitations, reflux, and blood pressure in sensitive users. Details
- Evidence
- Limited Evidence
- Typical onset
- Varies by prep
- Safety rating
- High caution
- Best for
- Antioxidant, Stress resilience
- Avoid / review if
- Uncontrolled Hypertension, Arrhythmia, Severe Anxiety/Insomnia
Safety
Safety & Cautions
Caffeine containing herb; may worsen insomnia, anxiety, palpitations, reflux, and blood pressure in sensitive users.
High caution
Caution level: High. Multiple caution categories apply, or the record uses avoid/contraindication language.
- Stimulant-Like ProfileStimulant-like or activating caution language is present.
- Pregnancy/Breastfeeding CautionPregnancy or breastfeeding caution language is present.
Detailed safety fields
Pregnancy, breastfeeding, and contraindications
- Uncontrolled Hypertension
- Arrhythmia
- Severe Anxiety/Insomnia
- Pregnancy/Breastfeeding Caution
- And Stimulant Sensitivity.
- Additive Effects With Caffeine
- Stimulants
- Theophylline
- Decongestants
- And Stimulant Medications.
Safety classifications
- Stimulant-Like Profile: Stimulant-like or activating caution language is present.
- Pregnancy/Breastfeeding Caution: Pregnancy or breastfeeding caution language is present.
Full safety note
- Caffeine containing herb; may worsen insomnia, anxiety, palpitations, reflux, and blood pressure in sensitive users.
Safety labels
- Stimulant-Like Profile
- 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
81 flagged pairingsBlood-pressure effects
Moderate Caution
81 flagged pairingsBlood-pressure effects
Representative pairings are shown below. Large mechanism groups are intentionally summarized to keep profiles focused and crawl-efficient.
Blood-pressure effectsCertainty: Theoretical
Data provenance recorded for 81 of 81 pairings in this mechanism group.
- Agmatine sulfate — Theoretical interaction certainty
- ajoene — Theoretical interaction certainty
- Allicin — Theoretical interaction certainty
- American Ginseng Extract — Theoretical interaction certainty
- Andrographis — Theoretical interaction certainty
- Angelica Dahurica — Theoretical interaction certainty
- Astaxanthin — Theoretical interaction certainty
- Astragalus Membranaceus — Theoretical interaction certainty
- Beetroot extract — Theoretical interaction certainty
- Berberis — Theoretical interaction certainty
- Bicarbonate — Theoretical interaction certainty
- Black Seed — Theoretical interaction certainty
+69 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: Present in source signals
Mechanistic / preclinical: Mechanism mapped — Oxidative Stress Modulation
Research maturity: Emerging research — Long Term Human Evidence May Be Limited.
Safety boundary: Safety note available — Caffeine containing herb; may worsen insomnia, anxiety, palpitations, reflux, and blood pressure in sensitive users.
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
- Randomized controlled trial
- Risk of Bias
- Low
- Consistency
- Not assessed
Strongest recorded design is a randomized controlled trial, drawn from 2 recorded studies, 1 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 (3)1 human evidence source · 1 human trial · Participant totals not consistently reported · Consistency not yet classifiable
Filter by study class
Showing 3 of 3 studies.
What the evidence actually shows
This table contains 3 structured sources, including 1 human evidence source; 1 is a human trial.
| Study | Design | N | Dose | Duration | Population | Outcome | Result & magnitude | Source |
|---|---|---|---|---|---|---|---|---|
La Monica MB et al. · Nutrients · 2023 Background | Randomized controlled trial Randomly assigns participants to interventions or controls, reducing many sources of bias when the trial is conducted well. | — | — | — | — | — | — | PubMed → |
Wise G et al. · Crit Rev Food Sci Nutr · 2020 Background | Narrative review Summarizes selected literature without the full prespecified search and selection methods of a systematic review. | — | — | — | — | — | — | PubMed → |
Sequeda-Castañeda LG et al. · Dent J (Basel) · 2024 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 Use moderate brewed preparations or products with disclosed caffeine content and require source backed dosage review before therapeutic claims.
How Guayusa works
Simplified mechanism pathway based on preclinical and pharmacological evidence. Does not confirm clinical efficacy.
Mechanism Pathway — How Guayusa Works
CompoundTarget / ReceptorMechanismEffect / Outcome
Mechanisms & biological pathways (preclinical)
- Oxidative Stress Modulation
Active Compounds
Key constituents studied in Guayusa, 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.
Review available sources for Guayusa
Independent database mapping — evaluated separately from safety and efficacy scores.
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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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