Skip to main content

Irinotecan Side Effects

Medically reviewed by Last updated on Sep 29, 2022.

Applies to irinotecan: intravenous solution.


Intravenous route (Solution)

Early and late forms of diarrhea can occur. Early diarrhea may be accompanied by cholinergic symptoms which may be prevented or ameliorated by atropine; late diarrhea can be life threatening and should be treated promptly with loperamide. Monitor patients with diarrhea and give fluid and electrolytes as needed. Institute antibiotic therapy if patients develop ileus, fever, or severe neutropenia. Interrupt irinotecan and reduce subsequent doses if severe diarrhea occurs. Severe myelosuppression may occur.

Serious side effects of Irinotecan

Along with its needed effects, irinotecan may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking irinotecan:

More common

  • Anxiety
  • black, tarry stools
  • blood in the urine or stools
  • blurred vision
  • changes in skin color
  • chest pain or discomfort
  • chest tightness or heaviness
  • chills
  • clay colored stools
  • cold hands and feet
  • confusion
  • constricted pupils
  • cough or hoarseness
  • dark urine
  • diarrhea with or without stomach cramps or sweating
  • dizziness
  • fainting
  • fast, slow, or irregular heartbeat
  • fever
  • full or bloated feeling or pressure in the stomach
  • headache
  • increased production of saliva
  • increased tear production
  • itching or skin rash
  • lightheadedness when getting up suddenly from a lying or sitting position
  • loss of appetite
  • low blood pressure or pulse
  • lower back or side pain
  • nausea or vomiting
  • numbness or tingling in the face, arms, or legs
  • pain
  • pain in the chest, groin, or legs, especially calves of the legs
  • pain in the shoulders, arms, jaw, or neck
  • painful or difficult urination
  • pale skin
  • pinpoint red spots on the skin
  • redness or swelling of the leg
  • runny nose
  • severe headache of sudden onset
  • slow breathing
  • slurred speech
  • sore throat
  • stomach pain
  • stopping of the heart
  • sudden and severe weakness in the arm or leg on one side of the body
  • sudden loss of coordination
  • sudden vision changes
  • sweating
  • swelling
  • swelling of the abdomen or stomach area
  • temporary blindness
  • tenderness, pain, or swelling of the arm, foot, or leg
  • troubled breathing
  • trouble with speaking or walking
  • ulcers, sores, or white spots on the lips or in the mouth
  • unconsciousness
  • unpleasant breath odor
  • unusual bleeding or bruising
  • unusual tiredness or weakness
  • vomiting of blood
  • warm, red feeling over the body
  • yellow eyes or skin

Less common

  • Bleeding gums
  • coughing up blood
  • decreased urination
  • difficulty with swallowing
  • dryness of the mouth
  • increased menstrual flow or vaginal bleeding
  • increased thirst
  • nosebleeds
  • paralysis
  • prolonged bleeding from cuts
  • sneezing
  • wrinkled skin


  • Decreased amount of urine
  • decreased frequency of urination
  • fast, irregular, or troubled breathing
  • hives
  • puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
  • rapid weight gain

Incidence not known

  • Abdominal or stomach pain and tenderness
  • agitation
  • bloated or full feeling
  • burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • coma
  • constipation
  • depression
  • heartburn or indigestion
  • hostility
  • irritability
  • lethargy
  • muscle pain and cramps
  • muscle twitching
  • pain in the stomach, side, or abdomen, possibly radiating to the back
  • pain or discomfort in the arms, jaw, back, or neck
  • rectal bleeding
  • severe abdominal or stomach cramping or burning
  • severe and continuing nausea
  • stupor
  • swelling of the face, lower legs, ankles, fingers, or hands
  • tightness in the chest
  • unusual tiredness or weakness
  • vomiting of material that looks like coffee grounds

Other side effects of Irinotecan

Some side effects of irinotecan may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

  • Acid or sour stomach
  • belching
  • blistering, peeling, redness, or swelling of the palms of hands or bottoms of the feet
  • cracked lips
  • excess air or gas in the stomach or intestines
  • feeling of constant movement of self or surroundings
  • numbness, pain, tingling, or unusual sensations in the palms of the hands or bottoms of feet
  • passing gas
  • right upper abdominal or stomach pain and fullness
  • sensation of spinning
  • sleepiness or unusual drowsiness
  • stomach discomfort, upset, or pain
  • trouble sleeping
  • weight loss

Incidence not known

For Healthcare Professionals

Applies to irinotecan: intravenous solution.


Very common (10% or more): Late diarrhea (23%), nausea (16%), dehydration (15%), abdominal pain (15%), Grade 3 diarrhea (15%), constipation, flatulence, stomatitis, dyspepsia, mucositis

Common (1% to 10%): Grade 4 diarrhea, early diarrhea, anorexia, constipation, abdominal enlargement

Uncommon (0.1% to 1%): Intestinal obstruction, ileus, megacolon, GI hemorrhage

Rare (less than 0.1%): Colitis, ischemic colitis, ulcerative colitis, pancreatitis[Ref]


Very common (10% or more): Neutropenia (54%) [Grade 3 neutropenia (30%), Grade 4 neutropenia (24%)], leucopenia (38%)

Common (1% to 10%): Anemia, neutropenic fever, thrombocytopenia, neutropenic infection, thrombophlebitis

Uncommon (0.1% to 1%): Biliary sepsis[Ref]


Very common (10% or more): Decreased appetite (49%), weight loss (20%), hypokalemia, hypomagnesemia, dehydration

Common (1% to 10%): Hypoglycemia, hyponatremia, hypophosphatemia, dehydration[Ref]


Very common (10% or more): Alopecia (22%), sweating, rash[Ref]


Very common (10% or more): Dyspnea, cough, rhinitis

Common (1% to 10%): Pneumonia, pulmonary embolism[Ref]

Nervous system

Very common (10% or more): Dizziness (23%), headache (17%)

Common (1% to 10%): Cholinergic syndrome, dysgeusia[Ref]


Common (1% to 10%): Hypotension, myocardial infarction

Uncommon (0.1% to 1%): Vasodilation

Postmarketing reports: Myocardial ischemic events[Ref]


Common (1% to 10%): Hypoalbuminemia, increased bilirubin, increased alanine aminotransferase, increased aspartate aminotransferase, increased international

Frequency not reported: Hepatic steatosis, steatohepatitis[Ref]


Very common (10% or more): Asthenia (20%), chills, edema

Common (1% to 10%): Pain, fever[Ref]


Uncommon (0.1% to 1%): Mild allergic reactions

Rare (less than 0.1%): Severe anaphylaxis[Ref]


Uncommon (0.1% to 1%): Renal insufficiency[Ref]


Very common (10% or more): Back pain (15%)[Ref]


Very common (10% or more): Bacterial, fungal. and viral infections[Ref]


Common (1% to 10%): Infusion related reaction[Ref]


Common (1% to 10%): Confusion[Ref]


1. "Product Information. Irinotecan Hydrochloride (irinotecan)." Areva Pharmaceuticals (2019):

Further information

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

Some side effects may not be reported. You may report them to the FDA.