What It Is

Irinotecan Hydrochloride Injection is a chemotherapy medication used to treat certain types of cancer.
It belongs to a class of drugs called topoisomerase I inhibitors and is most commonly used for colorectal cancer (cancer of the colon or rectum).

Composition

• Active ingredient: Irinotecan hydrochloride (in a sterile solution)

• Appearance: Clear, pale yellow solution

• Route: Given by intravenous (IV) infusion in a hospital or clinic

How It Works

Irinotecan works by:

1. Targeting Topoisomerase I enzyme – this enzyme helps unwind DNA during cell replication.

2. Blocking DNA replication in cancer cells – when the enzyme is blocked, DNA breaks accumulate.

3. Killing rapidly dividing cells – this slows or stops the growth of cancer.

Because it affects cell division, it can also affect some normal cells, which is why side effects can occur.

Uses / Indications

Irinotecan Hydrochloride is commonly used for:

• Metastatic colorectal cancer (spread beyond the colon/rectum)

• Often combined with other chemotherapy drugs such as 5-fluorouracil (5-FU) and leucovorin (regimen known as FOLFIRI)

• Sometimes used for other cancers (off-label) such as lung, gastric, or pancreatic cancer if recommended by oncologists

Administration

• Given by IV infusion over 30–90 minutes

• Usually administered every 1–3 weeks depending on the treatment regimen

• Dose is calculated based on body surface area (BSA), overall health, and previous treatment response

Possible Side Effects

Because it is a strong chemotherapy drug, side effects are common. These may include:

• Diarrhea (can be early-onset or delayed — may require special treatment)

• Nausea and vomiting

• Low white blood cell count (risk of infections)

• Hair loss

• Fatigue

• Abdominal pain or cramping

Rare but serious side effects:

• Severe dehydration from diarrhea

• Allergic reactions

• Lung problems (rare but possible)

Precautions

• Patients are monitored closely for white blood cell counts and hydration status

• Anti-nausea and anti-diarrheal medications are often given alongside treatment

• Not recommended in people with severe liver dysfunction without dose adjustment