Herb Profile

Grapefruit

Grapefruit carries a Grade C rating — limited evidence.

Last reviewed: Report a correctionProfile-wide ·C Limited

Use extra caution Major food drug interaction risk: can raise exposure of statins, calcium channel blockers, immunosuppressants, antiarrhythmics, and other CYP3A4/OATP substrates. Details

Evidence
Limited Evidence
Typical onset
Varies by prep
Safety rating
High caution
Best for
Digestive, Metabolic health
Avoid / review if
Avoid Or Medically Supervise With Drugs Labeled For Grapefruit Interaction, Narrow Therapeutic Index Drugs, And Complex Cardiovascular/Transplant Regimens.
Grapefruit monograph visual
Generated profile category visual

At a glance

From this profile's structured data
Evidence
Grade C
Safety
Major food-drug interaction risk: can raise exposure of statins, calcium-channel blockers, immunosuppressants, antiarrhythmics, and other CYP3A4/OATP substrates.
Profile context
digestive
Next steps

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Safety

Safety & Cautions

Major food drug interaction risk: can raise exposure of statins, calcium channel blockers, immunosuppressants, antiarrhythmics, and other CYP3A4/OATP substrates.

High caution

Caution level: High. Multiple caution categories apply, or the record uses avoid/contraindication language.

  • Interaction-AwareMedication or interaction context is explicitly noted.
Detailed safety fields

Pregnancy, breastfeeding, and contraindications

  • Avoid Or Medically Supervise With Drugs Labeled For Grapefruit Interaction
  • Narrow Therapeutic Index Drugs
  • And Complex Cardiovascular/Transplant Regimens.
  • CYP3A4
  • P Gp
  • And OATP Mediated Interactions
  • Effects May Persist Beyond A Single Serving.

Safety classifications

  • Interaction-Aware: Medication or interaction context is explicitly noted.

Full safety note

  • Major food drug interaction risk: can raise exposure of statins, calcium channel blockers, immunosuppressants, antiarrhythmics, and other CYP3A4/OATP substrates.

Safety labels

  • Interaction-Aware

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 mappedMetabolic Regulation

Research maturity: Theoretical / mechanistic researchMechanistic or unresolved evidence is kept separate from established human outcomes.

Safety boundary: Safety note availableMajor food drug interaction risk: can raise exposure of statins, calcium channel blockers, immunosuppressants, antiarrhythmics, and other CYP3A4/OATP substrates.

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

Dosing & Timing

No standardized dose
Preparation specific; use standardized product label for Interaction risk varies by whole fruit and require source backed dosage review before therapeutic claims.
How Grapefruit works

Simplified mechanism pathway based on preclinical and pharmacological evidence. Does not confirm clinical efficacy.

Mechanism Pathway — How Grapefruit Works

How Grapefruit WorksGrapefruit acts on biological target pathways via metabolic (regulation), leading to digestive.GrapefruitBiological TargetBiological pathwayMetabolicRegulationDigestiveObservable outcomeMitochondrialBiogenesis
CompoundTarget / ReceptorMechanismEffect / Outcome
Mechanisms & biological pathways (preclinical)
  • Metabolic Regulation

Active Compounds

Key constituents studied in Grapefruit, with full pharmacology and safety profiles.

Compare related active botanicals

Explore botanicals with similar chemistry, effects, or safety considerations in the Botanical Activity Atlas.

Guides that use Grapefruit

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.

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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