Irinotecan Hikma (Irinotecan Hydrochloride Trihydrate)

• Irinotecan Hikma is a Topoisomerase I inhibitor indicated for colorectal cancer therapy.
• Metastatic colorectal cancer: used as part of combination chemotherapy to improve overall survival.
• Advanced colorectal cancer: administered intravenously to inhibit tumor cell replication.
• Colorectal adenocarcinoma with disease progression: employed in regimens for patients who have failed prior therapy.

• Irinotecan is converted intracellularly to its active metabolite SN‑38, which binds to the DNA‑topoisomerase I complex. This stabilises the transient single‑strand breaks introduced during DNA replication, preventing relegation and resulting in irreversible DNA damage that triggers cell death in rapidly dividing cancer cells.

Irinotecan may cause a range of adverse reactions that vary in frequency and severity.

Common Side Effects

• Diarrhea: often severe and may require medical management.
• Nausea and vomiting: typical during and after infusion.
• Neutropenia: reduced white blood cell count increasing infection risk.
• Alopecia: temporary hair loss.
• Fatigue: generalized tiredness.
• Abdominal cramping: discomfort in the stomach area.

Serious or Rare Side Effects

• Severe neutropenic infection: febrile neutropenia requiring hospitalization.
• Acute cholinergic syndrome: sweating, salivation, bronchospasm.
• Hepatotoxicity: elevated liver enzymes.
• Severe mucositis: painful inflammation of the mouth lining.
• Hypersensitivity reactions: rash, dyspnea, anaphylaxis.
• Tumor lysis syndrome: metabolic disturbances from rapid tumor cell death.

• Before initiating therapy, clinicians should assess patient health status and monitor laboratory parameters.
• Baseline blood counts: obtain complete blood count and differential.
• Liver function: evaluate hepatic enzymes and bilirubin.
• Renal function: assess creatinine clearance for dose adjustments.
• Concurrent medications: review for agents that may increase toxicity.
• Pregnancy and lactation: avoid use unless benefits outweigh potential risks.
• Store at 2-8°C: keep refrigerated, protect from light, do not freeze or shake.

Irinotecan can interact with several drugs that affect its metabolism or toxicity profile.

Major Interactions (Avoid)

• Strong CYP3A4 inducers (e.g., rifampin): may reduce efficacy.
• Anticholinesterase agents (e.g., neostigmine): increase risk of cholinergic syndrome.
• High‑dose corticosteroids: may exacerbate neutropenia.

Moderate Interactions (Monitor Closely)

• UGT1A1 inhibitors (e.g., atazanavir): may raise SN‑38 levels.
• Antiemetics containing serotonin antagonists: potential additive nausea control.
• Warfarin: monitor INR for altered anticoagulation.
• Fluoropyrimidines: increased myelosuppression risk.
• Proton pump inhibitors: may affect gastric pH and absorption of oral supportive meds.