Topoisomerase I inhibitor
Irinotecan (Specialist drug)
Brand names: Camptosar, Onivyde
Adult dose
Dose: Specialist initiation only — refer to BNF/SmPC
Route: IV
Frequency: per protocol
Clinical pearls
- Colorectal, pancreatic cancer; loperamide for delayed diarrhoea
- Atropine for early cholinergic symptoms
Contraindications
- Severe bone marrow suppression
- Chronic IBD/intestinal obstruction
- Severe hepatic impairment
- Pregnancy
Side effects
- Severe diarrhoea (early cholinergic and delayed)
- Severe myelosuppression
- Cholinergic syndrome
- Nausea/vomiting
- Alopecia
Interactions
- UGT1A1 *28 polymorphism increases toxicity
- Strong CYP3A4 inducers/inhibitors
- Atazanavir
Monitoring
- FBC
- LFTs
- UGT1A1 testing in selected patients
Reference: BNF; SmPC; https://bnf.nice.org.uk/drugs/irinotecan-hydrochloride-specialist-drug/. Verify against your local formulary and the latest BNF before prescribing.
Related
Curated clinical cross-links plus same-class fallbacks.
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