Grapefruit
Aliases: Pomelo, Forbidden fruit
Summary
Bergamottin and 6',7'-dihydroxybergamottin in grapefruit irreversibly inactivate intestinal CYP3A4 via mechanism-based covalent binding, reducing enzyme abundance by 50-70% after a single 200 ml serving. Full resynthesis takes 24-72 hours, meaning timing separation of grapefruit and medication does not prevent interactions. Parallel inhibition of intestinal P-glycoprotein raises systemic exposure to many substrates, while OATP1A2 blockade can paradoxically lower absorption of drugs like fexofenadine.
Dose Information
| ROA | Light | Common | Strong | Heavy |
|---|---|---|---|---|
| Oral | 100-200ml | - | - | - |
Light
Common
Strong
Heavy
Onset, Duration & After-effects
| ROA | Onset | Comeup | Peak | Offset |
|---|---|---|---|---|
| Oral | 15-30 min | 30-60 min | 30 min | 24-24 hrs |
Tolerance
Build-up
varies by mechanism; therapeutic tolerance may develop over weeks of regular use
Reset
typically days to weeks after discontinuation
Tolerance Decay
Full tolerance
3d
Half tolerance
8d
Baseline
~14d
Effects
Positive
- Mild digestive stimulation
Neutral
- Bitter-sweet citrus flavor
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Pharmacology, chemical data, effect profiles, and more
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