Irinotecan Chemotherapy: Uses, Dosage, and Side Effects Explained

Summary or Key Points

Irinotecan is a chemotherapy drug used to treat several types of cancer, including colorectal, pancreatic, and small cell lung cancer. It works by interfering with the growth of cancer cells, helping to slow or stop their spread. Irinotecan is typically given through an IV (intravenous) infusion and may cause side effects such as nausea or diarrhea. Always consult your healthcare provider before starting or making any changes to your cancer treatment.

Names of Medication

US Brand Name: Camptosar

Generic Name: Irinotecan

The generic name refers to the active ingredient in the medication, while the brand name is assigned by the manufacturer. The generic name is listed in parentheses.

Pharmacologic Category

Topoisomerase I Inhibitors

Antineoplastic Agents

Irinotecan Dosage

Irinotecan is used to treat various cancers, and the dosage and frequency depend on the specific type of cancer being treated. Always consult your doctor before adjusting your dose. Our telemedicine providers are available to help manage your treatment plan.

Irinotecan Dosage for Colorectal Cancer

Dosage: 180 mg/m² IV every 2 weeks in combination with other chemotherapy agents.

Irinotecan Dosage for Pancreatic Cancer

Dosage: 70 mg/m² IV every 2 weeks in combination with other chemotherapy agents.

Irinotecan Dosage for Small Cell Lung Cancer

Dosage: 60 mg/m² IV on days 1, 8, and 15 of a 28-day cycle.

Irinotecan Dosage for Gastric Cancer

Dosage: 180 mg/m² IV every 2 weeks in combination with other chemotherapy agents.

Irinotecan Dosage for Ovarian Cancer

Dosage: 125 mg/m² IV every 3 weeks.

Irinotecan Dosage for Cervical Cancer

Dosage: 125 mg/m² IV every 3 weeks.

Irinotecan Dosage for Biliary Tract Cancer

Dosage: 180 mg/m² IV every 2 weeks in combination with other chemotherapy agents.

Irinotecan Dosage for Neuroendocrine Tumors

Dosage: 180 mg/m² IV every 2 weeks in combination with other chemotherapy agents.

Irinotecan Dosage for Esophageal Cancer

Dosage: 180 mg/m² IV every 2 weeks in combination with other chemotherapy agents.

Irinotecan Dosage for Head and Neck Cancer

Dosage: 125 mg/m² IV every 3 weeks.

Dosage Forms and Strengths

Injection, solution: 40 mg/2 mL (20 mg/mL)

Injection, solution: 100 mg/5 mL (20 mg/mL)

Administration Instructions for Irinotecan

Irinotecan is administered as an intravenous (IV) infusion, usually in a hospital or clinic setting. The infusion typically lasts about 90 minutes. It is important to follow your healthcare provider’s instructions carefully. You may be given medications beforehand to help prevent nausea or diarrhea. Staying well-hydrated and promptly reporting any severe side effects to your healthcare provider is essential for your safety.

Contraindications for Irinotecan

A contraindication is a condition or situation where a medication should not be used because it may cause harm. If you have any of the following conditions, you should not take Irinotecan, or you may need to discuss alternative treatments with your healthcare provider.

1. Severe allergic reaction to Irinotecan or its components: If you have experienced a severe allergic reaction to Irinotecan, taking it again could result in life-threatening symptoms such as difficulty breathing, hives, or swelling.
2. Severe liver disease: Irinotecan is processed by the liver. If your liver is not functioning properly, the medication can build up in your body, leading to serious side effects.
3. Severe bone marrow suppression: If your bone marrow is not producing enough blood cells, Irinotecan could worsen this condition, increasing the risk of life-threatening infections or bleeding.
4. Pregnancy: Irinotecan can harm an unborn baby, so it is contraindicated during pregnancy unless absolutely necessary. (More details in the pregnancy section below.)
5. Severe diarrhea: Irinotecan can cause or worsen diarrhea, which may lead to dehydration and other complications. If you already have severe diarrhea, your doctor may recommend waiting until it is under control before starting Irinotecan.

Drug to Drug Interactions with Irinotecan

Certain medications can interact with Irinotecan, either increasing the risk of side effects or reducing its effectiveness. It is important to inform your healthcare provider about all medications you are taking, including prescription drugs, over-the-counter medications, and supplements. Below are some common medications that can interact with Irinotecan:

1. Ketoconazole (Nizoral): This antifungal medication can increase the levels of Irinotecan in your body, leading to more severe side effects.
2. Phenytoin (Dilantin): This anti-seizure medication can reduce Irinotecan’s effectiveness by speeding up its breakdown in the liver.
3. Atazanavir (Reyataz): This HIV medication can also increase Irinotecan levels, raising the risk of side effects.
4. St. John’s Wort: This herbal supplement can reduce Irinotecan’s effectiveness by increasing its breakdown in the liver.

Irinotecan in Pregnancy

Is it Safe to Take Irinotecan During Pregnancy?

No, Irinotecan is not considered safe during pregnancy. It can harm an unborn baby, potentially causing birth defects or miscarriage. If you are pregnant or planning to become pregnant, discuss this with your healthcare provider before starting treatment. In some cases, the benefits of using Irinotecan may outweigh the risks, but this decision should be made carefully with your doctor. If you are of childbearing age, use effective birth control while taking Irinotecan and for a period after treatment ends, as recommended by your healthcare provider.

Irinotecan While Breastfeeding

Is it safe to take Irinotecan while breastfeeding?

No, it is not safe to breastfeed while taking Irinotecan. This medication can pass into breast milk and may pose serious risks to your baby. If you are currently breastfeeding or planning to do so, it is essential to consult your healthcare provider. They can help you explore alternatives, which may include stopping breastfeeding or postponing Irinotecan treatment until after you have weaned your baby.

Estimated Cost of Irinotecan

The cost of Irinotecan can vary depending on your location, pharmacy, and insurance coverage. Without insurance, a 30-day supply using a GoodRx coupon typically ranges from $150 to $300. Prices may fluctuate, so it’s a good idea to check with your pharmacy or use a discount service like GoodRx to find the most affordable option.

Possible Alternatives to Irinotecan

If Irinotecan is not suitable for you, or if you are considering other treatment options, there are alternative medications and lifestyle changes that may help manage your condition. Always consult your healthcare provider before making any changes to your treatment plan. You can also schedule a telemedicine appointment with one of our providers to discuss these alternatives in more detail.

Colorectal Cancer

For colorectal cancer, alternatives to Irinotecan include chemotherapy drugs such as Oxaliplatin (Eloxatin) or Capecitabine (Xeloda). Targeted therapies like Bevacizumab (Avastin) or immunotherapy may also be options. Additionally, maintaining a nutritious diet, engaging in regular physical activity, and avoiding smoking can support your overall health during treatment.

Pancreatic Cancer

For pancreatic cancer, other chemotherapy options include Gemcitabine (Gemzar) or the FOLFIRINOX regimen (a combination of four drugs). Radiation therapy and targeted therapies may also be considered. Incorporating lifestyle changes, such as a balanced diet and stress management techniques, can further enhance your well-being during treatment.

Small Cell Lung Cancer

For small cell lung cancer, alternatives to Irinotecan include Etoposide (Toposar) and Cisplatin (Platinol). Immunotherapy with drugs like Atezolizumab (Tecentriq) may also be an option. Quitting smoking and adopting a healthy lifestyle can significantly improve treatment outcomes.

Gastric Cancer

For gastric cancer, other chemotherapy options include 5-Fluorouracil (5-FU) or Cisplatin (Platinol). Targeted therapies and immunotherapy may also be considered. A healthy diet and regular physical activity can help support your treatment and overall well-being.

Ovarian Cancer

For ovarian cancer, alternatives to Irinotecan include Paclitaxel (Taxol) or Carboplatin (Paraplatin). Targeted therapies, such as Olaparib (Lynparza), may also be used. Maintaining a healthy weight and staying physically active can improve your overall health during treatment.

Cervical Cancer

For cervical cancer, other chemotherapy options include Cisplatin (Platinol) or Paclitaxel (Taxol). Radiation therapy and immunotherapy may also be considered. Regular exercise and a balanced diet can help support your treatment and improve your quality of life.

Biliary Tract Cancer

For biliary tract cancer, alternatives to Irinotecan include Gemcitabine (Gemzar) or Cisplatin (Platinol). Targeted therapies may also be an option. Maintaining a healthy lifestyle, including proper nutrition and physical activity, can improve your overall well-being during treatment.

Neuroendocrine Tumors

For neuroendocrine tumors, other treatment options include Everolimus (Afinitor) or Octreotide (Sandostatin). Surgery and targeted therapies may also be considered. A healthy diet and regular physical activity can help support your treatment and improve your overall health.

Esophageal Cancer

For esophageal cancer, alternatives to Irinotecan include 5-Fluorouracil (5-FU) or Cisplatin (Platinol). Radiation therapy and immunotherapy may also be considered. Quitting smoking and following a healthy lifestyle can improve your treatment outcomes and overall health.

Head and Neck Cancer

For head and neck cancer, other chemotherapy options include Cisplatin (Platinol) or Carboplatin (Paraplatin). Radiation therapy and immunotherapy may also be considered. Avoiding tobacco and alcohol, along with maintaining a healthy diet, can support your treatment and improve your overall well-being.

Recent Updates on Irinotecan Research

Recent research on Irinotecan is focused on enhancing its effectiveness while minimizing side effects. Studies are investigating the combination of Irinotecan with newer targeted therapies and immunotherapies to treat various cancers. For example, combining Irinotecan with immune checkpoint inhibitors is being explored to boost the body’s immune response against cancer cells. Researchers are also studying genetic markers that may help predict which patients will respond best to Irinotecan, paving the way for more personalized treatment plans.

Ongoing clinical trials are also examining the use of Irinotecan in cancers not traditionally treated with this drug, such as certain types of breast and liver cancer. These studies may lead to new treatment options in the future.

If you are interested in learning more about the latest research or clinical trials involving Irinotecan, speak with your healthcare provider. They can help determine if any of these developments are relevant to your treatment plan. You can also schedule a telemedicine appointment with one of our providers to discuss your options in greater detail.

James Kingsley

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