Irinotecan

Irinotecan is a prescription medicine used as first-line therapy (with 5-fluorouracil and leucovorin) for metastatic colorectal cancer (CRC) and for CRC that has recurred or progressed following initial fluorouracil-based therapy.

• Irinotecan is available under the following different brand names: Camptosar

Common side effects of Irinotecan include:

• nausea,
• vomiting,
• loss of appetite,
• constipation,
• cough,
• drowsiness,
• mouth sores,
• weakness,
• trouble sleeping, and
• temporary hair loss.

Serious side effects of Irinotecan include:

• hives,
• difficulty breathing,
• swelling of the face, lips, tongue, or throat,
• pain, redness, or swelling at the injection site or arms or legs,
• numbness, tingling, burning of arms or legs,
• back or bloody stools,
• change in the amount of urine,
• shortness of breath,
• cough,
• chest pain,
• weakness on one side of the body,
• trouble speaking,
• confusion,
• rash,
• itching, and
• severe dizziness.

Rare side effects of Irinotecan include:

• none 

Seek medical care or call 911 at once if you have the following serious side effects:

• Severe headache, confusion, slurred speech, arm or leg weakness, trouble walking, coordination loss, unsteady, very stiff muscles, high fever, profuse sweating, or tremors.
• Serious eye symptoms such as sudden vision loss, blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights.
• Serious heart symptoms include fast, irregular, or pounding heartbeats; fluttering in the chest; shortness of breath; sudden dizziness, lightheadedness, or passing out.

This is not a complete list of side effects and other serious side effects or health problems that may occur as a result of the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.

Adult dosage

• Liposomal dispersion for injection
  • 43 mg/10 mL single-dose vial

Pancreatic cancer

Adult dosage

• First-line treatment
  • Administer before oxaliplatin, fluorouracil, and leucovorin
  • Dose regardless of UGT1A1*28 allele genotype: 50 mg/m2 IV infused over 90 min every 2 weeks
  • No recommended dosage for patients with serum bilirubin above the upper limit of normal (ULN)
• Disease progression after gemcitabine-based treatment
  • Administer Irinotecan liposomal before leucovorin and fluorouracil
  • 70 mg/m2 IV infused over 90 min every 2 weeks
  • Patients known to be homozygous for the UGT1A1*28 allele: 50 mg/m2 IV infused over 90 min every 2 weeks; increase the dose to 70 mg/m2 as tolerated in subsequent cycles
  • Serum bilirubin above ULN: No recommended dose
  • Premedicate with a corticosteroid and an antiemetic agent 30 min before Irinotecan liposomal infusion

Dosage Considerations – Should be Given as Follows: 

• See “Dosages”

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first.

• Irinotecan has severe interactions with the following drugs:
  • carbamazepine
  • clozapine
  • cobicistat
  • conivaptan
  • darunavir
  • fosamprenavir
  • indinavir
  • itraconazole
  • lopinavir
  • rifampin
  • ritonavir
  • St John's Wort
• Irinotecan has serious interactions with at least 67 other drugs.
• Irinotecan has moderate interactions with at least 88 other drugs.
• Irinotecan has minor interactions with the following drugs: 
  • haloperidol
  • iloperidone
  • metronidazole
  • netupitant/palonosetron
  • valerian
  • vitamin A
  • vitamin E

This information does not contain all possible interactions or adverse effects. Visit the RxList Drug Interaction Checker for any drug interactions. Therefore, before using this product, tell your doctor or pharmacist about all the products you use. Keep a list of all your medications with you and share this information with your doctor and pharmacist. Check with your health care professional or doctor for additional medical advice, or if you have health questions or concerns.

Contraindications

• Hypersensitivity to drugs or excipients

Effects of drug abuse

• None

Short-Term Effects

• See “What Are Side Effects Associated with Using Irinotecan?”

Long-Term Effects

• See “What Are Side Effects Associated with Using Irinotecan?”

Cautions

• Can cause severe or life-threatening neutropenia and fatal neutropenic sepsis
• Can cause severe and life-threatening diarrhea; do not administer to patients with bowel obstruction
• Can cause severe and fatal interstitial lung disease; withhold drug in patients with new or progressive dyspnea, cough, and fever, pending diagnostic evaluation
• Severe hypersensitivity reactions may occur, including anaphylaxis; permanently discontinue if a severe hypersensitivity reaction occurs
• Based on animal data and the mechanism of action of Irinotecan liposomal, can cause fetal harm when administered to pregnant women
• Drug interaction overview
  • Strong CYP3A4 inducers
    • Avoid
      • Strong CYP3A4 inducers are known to substantially decrease systemic exposure to irinotecan or its active metabolite, SN-38
      • Substitute non-enzyme-inducing therapies at least 2 weeks before initiating irinotecan
  • Strong CYP3A4 or UGT1A1 inhibitors
    • Avoid
      • Strong CYP3A4 or UGT1A1 inhibitors have been shown to increase systemic exposure to irinotecan or its active metabolite, SN-38
      • Discontinue strong CYP3A4 inhibitors at least 1 week before initiating irinotecan

Pregnancy and Lactation

• Based on animal data and the mechanism of action, can cause fetal harm when administered to pregnant women
• Advise women of reproductive potential to use effective contraception during treatment and for 1 month after the final dose
• Contraception
  • Females: Advise women of reproductive potential to use effective contraception during treatment and for 7 months after the last dose
  • Males: Because of the potential for genotoxicity, advise men with women partners of reproductive potential to use condoms during treatment and for 4 months after the final dose
• Lactation
  • Unknown if distributed in human breast milk
  • Because of the potential for serious adverse reactions in breastfed infants from Irinotecan liposomal, advise a nursing woman not to breastfeed during treatment with and for 1 month after the final dose