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Clolar Side Effects

Generic Name: clofarabine

Note: This document contains side effect information about clofarabine. Some of the dosage forms listed on this page may not apply to the brand name Clolar.

In Summary

Common side effects of Clolar include: febrile neutropenia, herpes simplex infection, infection, oral candidiasis, pericardial effusion, pleural effusion, pneumonia, respiratory distress, sepsis, staphylococcal infection, abdominal pain, anxiety, arthralgia, back pain, cellulitis, confusion, constipation, cough, depression, dermatitis, diarrhea, dizziness, drowsiness, dyspnea, edema, epistaxis, erythrodysesthesia syndrome, fatigue, fever, gingival hemorrhage, headache, hematuria, hepatomegaly, hypertension, hypotension, jaundice, lethargy, limb pain, mucositis, myalgia, nausea, neutropenia, pain, petechia, pruritus, rigors, sore throat, tachycardia, transfusion reaction, tremor, vomiting, weight loss, anorexia, bacteremia, decreased appetite, erythema, flushing, irritability, pain at injection site, and xeroderma. Other side effects include: increased serum creatinine. See below for a comprehensive list of adverse effects.

For the Consumer

Applies to clofarabine: intravenous solution

Along with its needed effects, clofarabine (the active ingredient contained in Clolar) 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 clofarabine:

More common
  • Abdominal or stomach pain or tenderness
  • area rash
  • black, tarry stools
  • bleeding gums
  • blood in the urine or stools
  • bloody nose
  • blurred vision
  • burning or stinging of the skin
  • chest pain
  • chills
  • clay-colored stools
  • cold or flu-like symptoms
  • confusion
  • cough or hoarseness
  • dark urine
  • decreased urine output
  • diarrhea
  • difficult or labored breathing
  • dilated neck veins
  • dizziness
  • dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
  • facial swelling
  • fainting
  • fast, pounding, or irregular heartbeat or pulse
  • feeling of warmth
  • fever
  • flushing, redness of the skin
  • headache
  • irregular breathing
  • itching in the genital area
  • itching or skin rash
  • joint pain, stiffness, or swelling
  • lightheadedness
  • loss of appetite
  • lower back or side pain
  • nausea
  • nervousness
  • pain
  • painful cold sores or blisters on the lips, nose, eyes, or genitals
  • painful or difficult urination
  • pale skin
  • pinpoint red spots on the skin
  • pounding in the ears
  • rapid, shallow breathing
  • redness of the face, neck, arms, and occasionally, upper chest
  • redness, swelling, or skin pain
  • scaling of the skin on the hands and feet
  • severe abdominal or stomach cramps with pain
  • slow or fast heartbeat
  • small red or purple spots on the skin
  • sneezing
  • sore throat
  • sores, ulcers, or white spots on the lips or in the mouth
  • sweating
  • swelling of the ankles, feet, or lower legs
  • swelling or inflammation of the mouth
  • swollen glands
  • tenderness
  • tightness in the chest
  • tingling of the hands and feet
  • troubled breathing with exertion
  • ulcers, sores, or white spots in the mouth
  • unpleasant breath odor
  • unusual bleeding or bruising
  • unusual tiredness or weakness
  • unusually warm skin
  • vomiting
  • vomiting of blood
  • warmth on the skin
  • watery and severe diarrhea, which may also be bloody
  • weight gain
  • yellow eyes or skin
Less common
  • Agitation
  • bloating
  • blue lips and fingernails
  • chest pain or discomfort
  • cloudy urine
  • constipation
  • coughing that sometimes produces a pink frothy sputum
  • darkened urine
  • decrease or increase in the amount of urine
  • decreased level of consciousness
  • depression
  • difficult, fast, or noisy breathing, sometimes with wheezing
  • dry mouth
  • general feeling of discomfort or illness
  • hives
  • hostility
  • hyperventilation
  • increased sweating
  • indigestion
  • irritability
  • muscle aches and pains
  • muscle twitching
  • pain or tenderness around the eyes and cheekbones
  • pains in the stomach, side, or abdomen, possibly radiating to the back
  • rapid weight gain
  • restlessness
  • seizures (convulsions)
  • shaking
  • shivering
  • stuffy or runny nose
  • swelling of the eyelids, face, lips, or hands
  • trouble sleeping
Incidence not known
  • Blistering, peeling, or loosening of the skin
  • red irritated eyes
  • red skin lesions, often with a purple center

Some side effects of clofarabine 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
  • Back pain
  • bone pain
  • bruises on the skin
  • cracked lips
  • difficulty with moving
  • difficulty with swallowing
  • discouragement
  • dry skin
  • fear
  • feeling sad or empty
  • feeling unusually cold
  • injection site pain
  • itching, pain, redness, swelling, tenderness, or warmth on the skin at the injection site
  • lack or loss of strength
  • loss of interest or pleasure
  • muscle pain or stiffness
  • pain in the limbs
  • pain in the rectum
  • right upper stomach pain and fullness
  • skin discoloration
  • sore mouth or tongue
  • swollen joints
  • tiredness
  • trouble concentrating
  • unusual drowsiness, dullness, tiredness, weakness, or feeling of sluggishness
  • unusually warm skin
  • weight loss
  • white patches with diaper rash

For Healthcare Professionals

Applies to clofarabine: intravenous solution


Gastrointestinal side effects including vomiting (83%), nausea (75%), diarrhea (53%), abdominal pain (36%), anorexia (31%), constipation (21%), gingival bleeding (15%), sore throat (14%), and decreased appetite (11%) have been reported. Postmarketing reports have included gastrointestinal hemorrhage some with fatalities.[Ref]


A total of 85% of patients experienced at least one infection after clofarabine (the active ingredient contained in Clolar) treatment, including fungal, viral, and bacterial infections.[Ref]

Other side effects have included infections and infestations such as sepsis (15%), staphylococcal infection (13%), oral candidiasis (13%), herpes simplex (11%), cellulitis (11%), bacteremia (10%), and pneumonia (10%).

Several cases of capillary leak syndrome have been reported. (Signs and symptoms of cytokine release have included tachypnea, tachycardia, hypotension, and pulmonary edema.) Several patients developed rapid onset of respiratory distress, hypotension, capillary leak (pleural and pericardial effusions), and multi-organ failure.[Ref]


Hematologic side effects including febrile neutropenia (57%), neutropenia (10%), transfusion reactions (10%) and bone marrow failure have been reported.[Ref]


Dermatologic side effects including pruritus (47%), dermatitis (41%), petechiae (29%), erythema (18%), palmar-plantar erythrodysesthesia syndrome (13%), contusion (11%), and dry skin (10%) have been reported. Occurrences of Stevens-Johnson Syndrome (SJS) and toxic epidermal necrolysis (TEN) have been reported in patients who were receiving or had recently been treated with clofarabine (the active ingredient contained in Clolar) and other medications (e.g. allopurinol or antibiotics) known to cause these syndromes.[Ref]

Nervous system

Nervous system side effects including headache (46%), dizziness (16%), somnolence (10%), and tremor (10%) have been reported.[Ref]


Veno-occlusive disease has been reported in patients that received conditioning regimens that included busulfan, melphalan, and/or the combination of cyclophosphamide and total body irradiation.

Elevations of AST and ALT were transient and typically of less that 2 weeks duration.[Ref]

Hepatic side effects including jaundice (15%), hepatomegaly (15%), and veno-occlusive disease have been reported. Grade 3 or 4 elevated ALT (44%), grade 3 or 4 elevated AST (38%), and grade 3 or 4 elevated bilirubin (15%) have also been reported.[Ref]


General side effects including pyrexia (41%), rigors (38%), fatigue (36%), edema (20%), pain (19%), mucosal inflammation (18%), lethargy (11%), decreased weight (10%) and systemic inflammatory response syndrome (SIRS) have been reported.[Ref]


Cardiovascular side effects including pericardial effusion (35%), tachycardia (34%), left ventricular systolic dysfunction (27%), hypertension (3%), flushing (2%), and hypotension (1%) have been reported.[Ref]


Respiratory side effects including epistaxis (31%), cough (19%), respiratory distress (14%), dyspnea (13%), and pleural effusion (10%) have been reported.[Ref]


Musculoskeletal side effects including pain in limb (29%), myalgia (14%), back pain (13%), and arthralgia (11%) have been reported.[Ref]


Psychiatric side effects have been reported including anxiety (22%), depression (11%), and irritability (11%).[Ref]


Genitourinary side effects including hematuria (17%) have been reported.[Ref]


Local side effects including injection site pain (14%) have been reported.[Ref]


Renal side effects including grade 3 or 4 elevated creatinine (6%) have been reported.[Ref]


Oncologic side effects have included clastogenic activity in the in vitro mammalian cell chromosome aberration assay (CHO cells) and in the in vivo rat micronucleus assay.[Ref]


1. "Product Information. Clolar (clofarabine)." Genzyme Corporation, Cambridge, MA.

Some side effects of Clolar may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.