Food / CYP3A4 inhibitor
Grapefruit
Adult dose
Dose: N/A — counselling only
Route: PO
Frequency: avoid
Clinical pearls
- Counsel patients to avoid grapefruit/grapefruit juice with affected drugs — particularly statins, calcium-channel blockers, immunosuppressants
- Effect lasts 24–72h
Interactions
- Many — irreversibly inhibits intestinal CYP3A4 for ~72h. Affects amiodarone, tacrolimus, ciclosporin, simvastatin/atorvastatin, felodipine, nifedipine, verapamil, sildenafil, methadone, midazolam (oral), buspirone, triazolam, fexofenadine (P-gp/OATP), apixaban (caution)
Reference: BNF; UKMI medicines management; https://bnf.nice.org.uk/drugs/grapefruit/. Verify against your local formulary and the latest BNF before prescribing.
Related
Curated clinical cross-links plus same-class fallbacks.
Calculators
- SMART Risk Score for Recurrent CVD · Cardiovascular Risk
- PCSK9 Inhibitor Eligibility Assessment · Lipid Management
- Immune-Related Adverse Events (irAE) -- GI Toxicity Colitis Grading · Oncology-Related GI
- irAE Hepatitis Grading (CTCAE) · Immunotherapy
- DIPSS — Dynamic International Prognostic Scoring System for Myelofibrosis · Cancer Prognosis
- BALL Score for Relapsed/Refractory CLL · Leukaemia
Pathways
- Sepsis Screening and Sepsis Six · UK Sepsis Trust; NICE NG51; Surviving Sepsis Campaign 2021
- Unintentional Weight Loss Workup · NICE NG12; BSG
- Chronic Fatigue Workup · NICE NG206; BMJ Best Practice
- Lymphadenopathy Workup · NICE NG12; BMJ Best Practice
- Pre-op Medical Clearance · NICE NG45; ESC 2022
- Secondary Hypertension Workup · NICE NG136; ESH 2023