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Generic Name: irinotecan (EYE ri noe TEE kan)
Brand Name: Camptosar
Dosage Forms: intravenous solution (20 mg/mL)

Medically reviewed by on Sep 28, 2020. Written by Cerner Multum.

What is irinotecan?

Irinotecan is a cancer medicine that interferes with the growth and spread of cancer cells in the body.

Irinotecan is used to treat cancers of the colon and rectum. It is usually given with other cancer medicines in a combination chemotherapy.

Irinotecan may also be used for purposes not listed in this medication guide.


Irinotecan can cause severe diarrhea, which can be life-threatening if it leads to dehydration. You may be given medicines to prevent or quickly treat diarrhea.

Call your doctor whenever you have diarrhea during your treatment with irinotecan.

Before taking this medicine

You should not use irinotecan if you are allergic to it.

To make sure irinotecan is safe for you, tell your doctor if you have:

Do not use irinotecan if you are pregnant. It could harm the unborn baby. Use effective birth control, and tell your doctor if you become pregnant during treatment.

It is not known whether irinotecan passes into breast milk or if it could harm a nursing baby. You should not breast-feed while you are using irinotecan.

How is irinotecan given?

Your doctor may recommend a DNA test before your first dose of irinotecan. Some people are genetically more likely to have certain side effects from irinotecan.

Irinotecan is injected into a vein through an IV. A healthcare provider will give you this injection.

The IV infusion can take up to 90 minutes to complete. Tell your caregivers if you feel any burning, pain, or swelling around the IV needle.

If any of irinotecan gets on your skin, wash right away with soap and water.

You may be given medicine to prevent nausea, vomiting, diarrhea, and other side effects.

Irinotecan can cause severe diarrhea, which can be life-threatening if it leads to dehydration.

Your doctor may recommend you keep anti-diarrhea medicine (such as loperamide or Imodium) on hand at all times. Take the anti-diarrhea medicine at the first sign of loose or frequent bowel movements. Do not take loperamide for longer than 2 full days without your doctor's advice.

Call your doctor whenever you have diarrhea during your treatment with irinotecan.

You may need frequent medical tests to be sure this medicine is not causing harmful effects. Your cancer treatments may be delayed based on the results of these tests.

If you need surgery, tell the surgeon ahead of time that you are using irinotecan.

What happens if I miss a dose?

Call your doctor for instructions if you miss an appointment for your irinotecan injection.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while using irinotecan?

Avoid using a laxative or stool softener during treatment with irinotecan.

Avoid being near people who are sick or have infections. Tell your doctor at once if you develop signs of infection.

Do not receive a "live" vaccine while using irinotecan, and avoid coming into contact with anyone who has recently received a live vaccine. There is a chance that the virus could be passed on to you. Live vaccines include measles, mumps, rubella (MMR), polio, rotavirus, typhoid, yellow fever, varicella (chickenpox), zoster (shingles), and nasal flu (influenza) vaccine.

Irinotecan may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

irinotecan can pass into body fluids (urine, feces, vomit). For at least 48 hours after you receive a dose, avoid allowing your body fluids to come into contact with your hands or other surfaces. Caregivers should wear rubber gloves while cleaning up a patient's body fluids, handling contaminated trash or laundry or changing diapers. Wash hands before and after removing gloves. Wash soiled clothing and linens separately from other laundry.

Irinotecan side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Also call your doctor at once if you have:

  • severe or ongoing vomiting or diarrhea;

  • nausea or vomiting that keeps you from drinking enough fluids;

  • sudden chest pain or discomfort, wheezing, dry cough, feeling short of breath;

  • pain, redness, numbness, and peeling skin on your hands or feet;

  • dehydration symptoms--feeling very thirsty or hot, being unable to urinate, heavy sweating, or hot and dry skin; or

  • low blood cell counts--fever, chills, flu-like symptoms, swollen gums, mouth sores, skin sores, rapid heart rate, pale skin, easy bruising, unusual bleeding, feeling light-headed.

Common side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Irinotecan dosing information

Usual Adult Dose for Colorectal Cancer:

125 mg/m2 IV over 90 minutes on Days 1, 8,15, and 22 with LV 20 mg/m2 IV bolus on Days 1, 8, 15, and 22 followed by 5-FU 500 mg/m2 IV bolus on Days 1, 8, 15, and 22 every 6 weeks

180 mg/m2 IV over 90 minutes on Days 1, 15, and 29 with LV 200 mg/m2 IV over 2 hours on Days 1, 2, 15, 16, 29, and 30 followed by 5-FU 400 mg/m2 IV bolus on Days 1, 2, 15, 16, 29, and 30 and 5-FU 600 mg/m2 IV over 22 hours on Days 1, 2, 15, 16, 29, 30 (NOTE: 5-FU IV follows 5-FU bolus)

125 mg/m2 IV over 90 minutes on Days 1, 8, 15, and 22 then 2-week rest

350 mg/m2 IV over 90 minutes on Day 1 every 3 weeks

-It is recommended that patients receive premedication with antiemetics (e.g., 10 mg dexamethasone given in conjunction with another antiemetic agent, such as a 5-HT 3 blocker [e.g., ondansetron or granisetron]).
-Antiemetic agents should be given at least 30 minutes before this drug.
-Physicians should consider providing patients with an antiemetic regimen (e.g., prochlorperazine) for subsequent use as needed.
-A similar antiemetic regimen should be used with combination therapy.
-Prophylactic or therapeutic administration of atropine should be considered in patients experiencing cholinergic symptoms.

-First-line therapy in combination with 5-fluorouracil (5-fu) and leucovorin (LV) for patients with metastatic carcinoma of the colon or rectum
-Patients with metastatic carcinoma of the colon or rectum whose disease has recurred or progressed following initial fluorouracil-based therapy

What other drugs will affect irinotecan?

Before you are treated with irinotecan, tell your doctor about all other cancer medicines you have recently used.

Tell your doctor about all your current medicines and any you start or stop using, especially:

This list is not complete. Other drugs may interact with irinotecan, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.