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Rebetron Side Effects

Generic name: interferon alfa-2b / ribavirin

Note: This document contains side effect information about interferon alfa-2b / ribavirin. Some dosage forms listed on this page may not apply to the brand name Rebetron.

Applies to interferon alfa-2b/ribavirin: oral and injectable kit.


Interferon alfa-2b-ribavirin therapy was discontinued in 19% and 6% of previously untreated and relapse patients, respectively, during clinical trials. In comparison, 13% of previously untreated patients and 3% of relapse patients discontinued therapy in the interferon arms.

Alpha interferons, including interferon alfa-2b, have caused or aggravated fatal or life-threatening neuropsychiatric, autoimmune, ischemic, and infectious disorders. In many but not all cases these disorders resolved after stopping interferon alfa-2b.[Ref]


Hemolytic anemia is the primary toxicity of ribavirin therapy. Hemoglobin levels generally declined within the first 1 to 2 weeks of ribavirin therapy. Cardiac and pulmonary events associated with anemia have been reported in about 10% of patients.

The mean maximum decrease from baseline hemoglobin levels observed in US and international studies ranged from 2.6 g/dL to 3.1 g/dL. Hemoglobin values returned to pretreatment levels within 4 to 8 weeks of cessation of therapy in most patients. Neutrophil and platelet values returned to pretreatment levels within 4 weeks after treatment discontinuation.[Ref]

Hematologic side effects have included decreased hemoglobin (9.5 to 10.9 g/dL: up to 32%; 8 to 9.4 g/dL: up to 5%), leukocytes [2 to 2.9 x 10(9)/L: up to 45%; 1.5 to 1.9 x 10(9)/L: up to 9%; 1 to 1.4 x 10(9)/L: up to 2%], neutrophils [1 to 1.49 x 10(9)/L: up to 42%; 0.75 to 0.99 x 10(9)/L: up to 16%; 0.5 to 0.74 x 10(9)/L: up to 14%; less than 0.5 x 10(9)/L: up to 11%], and platelets [70 to 99 x 10(9)/L: up to 11%; 50 to 69 x 10(9)/L: up to 2%; less than 30 x 10(9)/L: up to 1%]. Bone marrow function suppression, which may result in severe cytopenias, has been reported with interferon alfa-2b therapy. Hemolytic anemia (hemoglobin less than 10 g/dL) was observed in approximately 10% of patients on combination therapy in clinical trials. Aplastic anemia has been rarely reported with interferon alfa-2b-ribavirin therapy.[Ref]


Cardiac and pulmonary events associated with anemia have been reported in about 10% of patients.[Ref]

Respiratory side effects have included dyspnea (up to 19%) and sinusitis (up to 12%). Pulmonary symptoms (including dyspnea, pulmonary infiltrates, pneumonitis, pulmonary hypertension, pneumonia, and fatal pneumonia), sarcoidosis, and exacerbation of sarcoidosis have been reported.[Ref]


Cardiovascular side effects have included deterioration of cardiac function and/or exacerbation of the symptoms of coronary disease due to the anemia associated with interferon alfa-2b-ribavirin therapy.[Ref]

Cardiac and pulmonary events associated with anemia have been reported in about 10% of patients.[Ref]


Psychiatric side effects have included insomnia (up to 39%), depression (up to 36%), irritability (up to 32%), impaired concentration (up to 14%), emotional lability (up to 12%), and nervousness (up to 5%). Suicidal behavior (including ideation, attempts, and suicides) has been reported in 1% of patients. Severe psychiatric side effects, including depression, psychoses, aggressive behavior, hallucinations, violent behavior (suicidal ideation, suicidal attempts, suicides), and rare cases of homicidal ideation, have been reported in patients with and without previous psychiatric disorder.[Ref]

Nervous system

Nervous system side effects have included headache (up to 66%), dizziness (up to 26%), and taste perversion (up to 8%). Hearing disorders (including tinnitus and hearing loss) and vertigo have been reported in postmarketing studies.[Ref]


Gastrointestinal side effects have included nausea (up to 47%), anorexia (up to 27%), dyspepsia (up to 16%), and vomiting (up to 12%). Pancreatitis, including fatal and nonfatal, has been observed.[Ref]


Musculoskeletal side effects have included myalgia (up to 64%), arthralgia (up to 33%), and musculoskeletal pain (up to 28%).[Ref]


Ocular side effects induced or aggravated by alpha interferon therapy have included decrease or loss of vision, retinopathy including macular edema, retinal artery or vein thrombosis, retinal hemorrhages and cotton wool spots, optic neuritis, papilledema, and serous retinal detachment.[Ref]


Hypersensitivity side effects have included acute serious hypersensitivity reactions (e.g., urticaria, angioedema, bronchoconstriction, and anaphylaxis) in patients treated with interferon alfa-2b.[Ref]


Dermatologic side effects have included alopecia (up to 32%), rash (up to 28%), and pruritus (up to 21%). Exacerbation of preexisting psoriasis has been reported. Transient rashes have been reported in some patients following interferon alfa-2b injection.[Ref]


A case report of hyperthyroidism, manifested in the form of thyroiditis, in a 28-year-old woman responding well to interferon alfa-2b-ribavirin therapy, suggested that temporary interferon alfa-2b dose reduction and symptomatic treatment may be all that is needed in destructive thyroiditis.[Ref]

Endocrine side effects have included thyroid abnormalities, including hypothyroidism and hyperthyroidism. Thyroiditis has been reported.[Ref]


Local side effects have included injection site inflammation (up to 13%) and injection site reaction (up to 8%).[Ref]


Most cases of increased bilirubin and uric acid were moderate biochemical changes, reversed within 4 weeks after treatment discontinuation, and were not associated with hepatic dysfunction or clinical morbidity.[Ref]

Other side effects have included fatigue (up to 70%), rigors (up to 43%), fever (up to 41%), influenza-like symptoms (up to 18%), asthenia (up to 10%), and chest pain (up to 9%). Increases in both bilirubin and uric acid, associated with hemolysis, have been reported in clinical trials. Elevated total bilirubin (1.5 to 3 mg/dL: up to 32%; 3.1 to 6 mg/dL: up to 3%; 6.1 to 12 mg/dL: up to 0.4%) has been reported.[Ref]


Immunologic side effects have included exacerbation of autoimmune disease in patients receiving interferon alfa-2b.


Metabolic side effects have included elevated triglycerides, hyperglycemia, new onset diabetes mellitus, exacerbation of preexisting diabetes mellitus, and diabetic ketoacidosis.[Ref]

Diabetic ketoacidosis was reported in a 53-year-old white female after week 24 of treatment, who had in the first 12 weeks of treatment normal random blood glucose limits (less than 110 mg/dL), and required insulin. Interferon alfa-2b-ribavirin was stopped.[Ref]

More about Rebetron (interferon alfa-2b / ribavirin)

Related treatment guides


1. "Product Information. Rebetron (interferon alfa-2b-ribavirin)." Scherer Laboratories Inc

2. Poynard T, Marcellin P, Lee SS, Niederau C, Minuk GS, Ideo G, Bain V, Heathcote J, Zeuzem S, Trepo C, Albrecht J "Randomised trial of interferon alpha 2b plus ribavirin for 48 weeks or for 24 weeks versus interferon alpha 2b plus placebo for 48 weeks for treatment of chronic infection with hepatitis C virus." Lancet 352 (1998): 1426-32

3. Malik UR, Makower DF, Wadler S "Interferon-mediated fatigue." Cancer 92(6 Suppl) (2001): 1664-8

4. Barbaro G, DiLorenzo G, Belloni G, Ferrari L, Paiano A, DelPoggio P, Bacca D, Fruttaldo L, Mongio F, Francavilla R, Scotto G, Gr "Interferon alpha-2B and ribavirin in combination for patients with chronic hepatitis C who failed to respond to, or relapsed after, interferon alpha therapy: A randomized trial." Am J Med 107 (1999): 112-8

5. Liang TJ, Rehermann B, Seeff LB, Hoofnagle JH "Pathogenesis, natural history, treatment, and prevention of hepatitis C." Ann Intern Med 132 (2000): 296-305

6. Lauer GM, Walker BD "Hepatitis C virus infection." N Engl J Med 345 (2001): 41-52

7. James CW, Savini CJ "Homicidal ideation secondary to interferon." Ann Pharmacother 35(7-8) (2001): 962-3

8. Sookoian S, Neglia V, Castano G, Frider B, Kien MC, Chohuela E "High prevalence of cutaneous reactions to interferon alfa plus ribavirin combination therapy in patients with chronic hepatitis C virus." Arch Dermatol 135 (1999): 1000-1

9. Sachithanandan S, Clarke G, Crowe J, Fielding JF "Interferon-associated thyroid dysfunction in anti-D-related chronic hepatitis C." J Interferon Cytokine Res 17 (1997): 409-11

10. Harris DM, Hespenheide EE, Dalkin AC, Kirk SE, Ellis DS, Caldwell SH "Hyperthyroidism with interferon-ribavirin therapy for hepatitis C: A case report and proposed treatment algorithm." Am J Gastroenterol 95 (2000): 2995-6

11. Bhatti A, McGarrity TJ, Gabbay R "Diabetic ketoacidosis induced by alpha interferon and ribavirin treatment in a patient with hepatitis C." Am J Gastroenterol 96 (2001): 604-5

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.