Irinotecanhydrochlorid 3 H2o Phares (Irinotecan Hydrochloride Trihydrate)

Irinotecan Hydrochloride Trihydrate is a topoisomerase I inhibitor used in the management of colorectal cancer.

• Metastatic colorectal cancer: prolongs progression‑free and overall survival when given with fluoropyrimidine regimens.
• Refractory colorectal cancer: provides disease control in patients whose disease has progressed after prior therapy.
• Combination therapy for advanced colorectal cancer: enhances tumor response rates as part of multi‑agent chemotherapy protocols.

• Irinotecan is a prodrug that is converted intracellularly to SN‑38, a potent inhibitor of topoisomerase I. By stabilizing the topoisomerase‑DNA cleavable complex, SN‑38 prevents relegation of single‑strand DNA breaks during replication, leading to accumulation of DNA damage, replication arrest and ultimately tumor cell apoptosis. The effect is cell‑cycle dependent, primarily affecting cells in S‑phase, and the drug’s activity is modulated by hepatic carboxylesterases and glucuronidation pathways that influence SN‑38 exposure.

Irinotecan may cause a range of adverse reactions, varying in frequency and severity.

Common Side Effects

• Diarrhea: often severe and may require antidiarrheal therapy.
• Nausea and vomiting: typical chemotherapy‑related gastrointestinal symptoms.
• Neutropenia: reduced white blood cell count increasing infection risk.
• Alopecia: temporary hair loss during treatment.
• Fatigue: generalized tiredness affecting daily activities.
• Abdominal pain: discomfort in the stomach region.

Serious or Rare Side Effects

• Febrile neutropenia: fever with low neutrophil count requiring urgent care.
• Severe colitis (including ileus): inflammatory bowel complications.
• Hepatotoxicity: elevated liver enzymes indicating liver injury.
• Hypersensitivity reactions: rash, bronchospasm, or anaphylaxis.

When using Irinotecan, several precautions should be observed to minimize risks and ensure safe administration.

• Pre‑treatment assessment: evaluate baseline blood counts and liver function tests.
• Monitor for neutropenia: perform regular complete blood counts during therapy.
• Manage diarrhea proactively: initiate loperamide at first sign of loose stools.
• Adjust dose in hepatic impairment: consider reduced dosing for patients with elevated bilirubin.
• Avoid concurrent strong CYP3A4 inhibitors: they may increase SN‑38 exposure.
• Store at 2‑8 °C: keep refrigerated, protect from light, do not freeze or shake.

Irinotecan can interact with other medicines, affecting its efficacy or toxicity.

Major Interactions (Avoid)

• Strong CYP3A4 inhibitors (e.g., ketoconazole, ritonavir): may raise SN‑38 levels and increase toxicity.
• UGT1A1 inhibitors (e.g., atazanavir): can reduce SN‑38 glucuronidation, heightening risk of neutropenia and diarrhea.
• Concurrent use of other myelosuppressive agents: may exacerbate bone‑marrow suppression.

Moderate Interactions (Monitor Closely)

• Anticoagulants (warfarin, DOACs): increased bleeding risk due to mucosal injury.
• Antidiarrheal agents (loperamide) at high doses: may affect drug clearance.
• CYP3A4 inducers (e.g., rifampicin, carbamazepine): may lower SN‑38 exposure, reducing efficacy.