Grapefruit
Limited data
Limited data
Sparse data. Doses and effects may be unreliable or untested.
- 1 source
- partial dose data
- duration data present
- dose data not in PW/TripSit (unverifiable)
- 1 source
- partial dose data
- duration data present
- dose data not in PW/TripSit (unverifiable)
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 | - | - | - |
Onset, Duration & After-effects
| ROA | Onset | Comeup | Peak | Offset |
|---|---|---|---|---|
| Oral | 15-30 min | 30-60 min | 30 min | 24 hrs |
Tolerance
Tolerance Decay
Acute tolerance: develops within a single session — the reset numbers above apply after sustained heavy use, not after one binge. Within-session tachyphylaxis usually resets largely overnight.
Effects
- Mild digestive stimulation
- Bitter-sweet citrus flavor
Helpful Links
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