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Oforta Side Effects

Generic Name: fludarabine

Note: This page contains side effects data for the generic drug fludarabine. It is possible that some of the dosage forms included below may not apply to the brand name Oforta.

For the Consumer

Applies to fludarabine: oral tablet

As well as its needed effects, fludarabine (the active ingredient contained in Oforta) may cause unwanted side effects that require medical attention.

Severity: Major

If any of the following side effects occur while taking fludarabine, check with your doctor immediately:

More common:
  • Bloating or swelling of the face, arms, hands, lower legs, or feet
  • body aches or pain
  • burning or stinging of the skin
  • chest pain
  • cough or hoarseness
  • cough producing mucus
  • diarrhea
  • difficult or labored breathing
  • difficulty in breathing
  • ear congestion
  • fever or chills
  • general feeling of discomfort or illness
  • headache
  • joint pain
  • loss of appetite
  • loss of voice
  • lower back or side pain
  • muscle aches and pains
  • nasal congestion
  • nausea
  • painful cold sores or blisters on the lips, nose, eyes, or genitals
  • painful or difficult urination
  • rapid weight gain
  • runny nose
  • shivering
  • shortness of breath
  • sneezing
  • sore throat
  • stuffy nose
  • sweating
  • tightness in the chest
  • tingling of hands or feet
  • trouble sleeping
  • troubled breathing
  • unusual tiredness or weakness
  • unusual weight gain or loss
  • vomiting
  • wheezing
Less common:
  • Bladder pain
  • bloody or cloudy urine
  • difficult, burning, or painful urination
  • frequent urge to urinate
  • pain or tenderness around the eyes and cheekbones
Incidence not known:
  • Back pain
  • bloody, black, or tarry stools
  • blue lips, fingernails, or skin
  • blurred vision
  • confusion
  • convulsions
  • coughing up blood
  • difficult or fast breathing
  • dizziness
  • drowsiness
  • high fever
  • irregular, fast or slow, or shallow breathing
  • pale skin
  • sores, ulcers, or white spots on the lips or in the mouth
  • swollen glands
  • unexplained bleeding or bruising
  • unusual bleeding or bruising

Severity: Minor

Some fludarabine side effects may not need any medical attention. As your body gets used to the medicine these side effects may disappear. Your health care professional may be able to help you prevent or reduce these side effects, but do check with them if any of the following side effects continue, or if you are concerned about them:

More common:
  • Abdominal pain
  • increased sweating
  • weight loss
Less common:
  • Rash

For Healthcare Professionals

Applies to fludarabine: intravenous powder for injection, intravenous solution, oral tablet


In general, the most common dose-limiting toxicities have been myelosuppression (60%), fever and chills (11% to 60%, sometimes without infection), infection (33%, including serious opportunistic infections), and nausea and vomiting (36%).

General side effects including pain (up to 19%), flu syndrome (up to 8%), and decreased weight (up to 6%) have been reported.[Ref]


Instances of life-threatening and sometimes fatal autoimmune hemolytic anemia have been reported after one or more cycles of treatment in patients with or without a previous history of autoimmune hemolytic anemia or a positive Coombs test and who may or may not be in remission for their disease. Steroids may be effective in controlling these hemolytic episodes. The majority of affected patients developed a recurrence upon rechallenge.

An increased incidence of infections with pathogens not commonly associated with chronic lymphocytic leukemia have been associated with the use of fludarabine (the active ingredient contained in Oforta) especially when given with corticosteroids. These have included Listeria, Pneumocystis carinii pneumonia, disseminated varicella-zoster, cytomegalovirus, and unusual fungal pathogens. Fludarabine can significantly decrease the quantity of T-helper cells.[Ref]

Immunologic side effects have been reported secondary to neutropenia which predisposes patients to infection. Pneumonia has been reported in 16% to 22% of treated patients from major clinical trials. Other, less common, infections include minor bacterial and/or fungal infections of the oropharynx, upper respiratory tract, urinary tract, and soft tissue, as well as herpes zoster infections. The risk of sepsis or life-threatening infection appears greatest during the first three courses of chemotherapy with fludarabine in patients with extensive disease.[Ref]

Nervous system

Central and peripheral nervous system toxicities have been reported, including weakness/fatigue (asthenia) (up to 31%), headache (up to 9%), hearing disturbances (6%), paresthesias (4%), confusion (1%), visual disturbances (3%), and coma (less than 1%). In postmarketing experience, cases of progressive multifocal leukoencephalopathy have been reported. Rare cases of disabling, severe, but reversible neurologic toxicity have been reported.[Ref]


Renal side effects including hemolytic uremic syndrome and acute renal failure have rarely been associated with the use of fludarabine (the active ingredient contained in Oforta) [Ref]


Hypersensitivity reactions--usually skin rashes-- to fludarabine (the active ingredient contained in Oforta) are relatively rare. Corticosteroid-responsive acute interstitial pulmonary infiltrates have been reported. Extremely rare cases of anaphylaxis have been reported.[Ref]


TLS may result in serious metabolic problems, including hyperuricemia, hyperphosphatemia, hypocalcemia, metabolic acidosis, hyperkalemia, hematuria, urate crystalluria, renal failure, and even death. (Allopurinol before and during therapy is recommended.) The onset of this syndrome may be heralded by flank pain and hematuria.[Ref]


Dermatologic side effects including increased sweating (up to 14%), diaphoresis (up to 8%), skin disorder (up to 6%), and rash (up to 5%) have been reported. Alopecia has been reported only rarely.[Ref]


Musculoskeletal side effects including back pain (up to 9%) have been reported.


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4. "Product Information. Fludara (fludarabine)." Berlex, Richmond, CA.

5. Chim CS, Liang R, Wong SSY, Yuen KY "Cryptococcal infection associated with fludarabine therapy." Am J Med 108 (2000): 523-4

6. Anaissie EJ, Kontoyiannis DP, O'Brien S, et al. "Infections in patients with chronic lymphocytic leukemia treated with fludarabine." Ann Intern Med 129 (1998): 559-66

7. Zabernigg A, Maier H, Thaler J, Gattringer C "Late-onset fatal neurological toxicity of fludarabine." Lancet 344 (1994): 1780

8. Johnson PW, Fearnley J, Domizio P, Goldin J, Nagendran K, Gawler J, Rohatiner AZ, Lister TA "Neurological illness following treatment with fludarabine." Br J Cancer 70 (1994): 966-8

9. Cohen RB, Abdallah JM, Gray JR, Foss F "Reversible neurologic toxicity in patients treated with standard-dose fludarabine phosphate for mycosis fungoides and chronic lymphocytic leukemia." Ann Intern Med 118 (1993): 114-6

10. Merkel DE, Griffin NL, Kagan-Hallet K, Von Hoff DD "Central nervous system toxicity with fludarabine." Cancer Treat Rep 70 (1986): 1449-50

11. Hocepied AMLJ, Falkson CI, Falkson G "A phase II trial of fludarabine in patients with previously treated chronic lymphocytic leukaemia." S Afr Med J 86 (1996): 549-50

12. Montillo M, Tedeschi A, Leoni P "Acute renal failure as a consequence of urine stop flow in a patient with chronic lymphocytic leukemia after treatment with fludarabine." Am J Hematol 50 (1995): 73-4

13. Nunes R, Passos-Coelho JL, Miranda N, Nave M, Leal Da Costa F, Abecasis M "Reversible acute renal failure following single administration of fludarabine." Bone Marrow Transplant (2004):

14. Macheta MP, Parapia LA, Gouldesbrough DR "Renal failure in a patient with chronic lymphocytic leukaemia treated with fludarabine." J Clin Pathol 48 (1995): 181-2

15. Cohn J, Fraifeld M, Desai A, Zaeri N "Hemolytic uremic syndrome (HUS) and severe pulmonary toxicity associated with fludarabine treatment for non-Hodgkin's lymphoma (NHL) (Meeting abstract)." Proc Annu Meet Am Soc Clin Oncol 13 (1994): a13161994

16. List AF, Kummet TD, Adams JD, Chun HG "Tumor lysis syndrome complicating treatment of chronic lymphocytic leukemia with fludarabine phosphate." Am J Med 89 (1990): 388-90

17. Nakhoul F, Green J, Abassi ZA, Carter A "Tumor lysis syndrome induced by fludarabine monophosphate: a case report." Eur J Haematol 56 (1996): 254-5

18. Frame JN, Dahut WL, Crowley S "Fludarabine and acute tumor lysis in chronic lymphocytic leukemia." N Engl J Med 327 (1992): 1396-7

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21. Kavanagh JJ, Krakoff IH, Bodey GP "Phase I study of fludarabine (2-fluoro-ara-AMP)." Eur J Cancer Clin Oncol 21 (1985): 1009-11

It is possible that some side effects of Oforta may not have been reported. These can be reported to the FDA here. Always consult a healthcare professional for medical advice.

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.