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Rebif Side Effects

Generic Name: interferon beta-1a

Note: This page contains side effects data for the generic drug interferon beta-1a. It is possible that some of the dosage forms included below may not apply to the brand name Rebif.

In Summary

Common side effects of Rebif include: flu-like symptoms, fever, headache, myalgia, nausea, and chills. Other side effects include: anemia. See below for a comprehensive list of adverse effects.

For the Consumer

Applies to interferon beta-1a: kit, solution

As well as its needed effects, interferon beta-1a (the active ingredient contained in Rebif) may cause unwanted side effects that require medical attention.

Major Side Effects

If any of the following side effects occur while taking interferon beta-1a, check with your doctor immediately:

More common:
  • Black, tarry stools
  • chest pain
  • chills
  • cough
  • diarrhea
  • fever
  • flu-like symptoms
  • headache
  • joint pain
  • muscle aches
  • nausea
  • pain
  • painful or difficult urination
  • shortness of breath
  • sores, ulcers, or white spots on the lips or in the mouth
  • swollen glands
  • unusual bleeding or bruising
  • unusual tiredness or weakness
Less common:
  • Abdominal or stomach pain
  • clumsiness or unsteadiness
  • convulsions (seizures)
  • decreased hearing
  • difficulty with swallowing
  • dizziness
  • fainting
  • feeling of warmth
  • hives or itching
  • mood changes, especially with thoughts of suicide
  • muscle spasms
  • pain or discharge from the vagina
  • pelvic discomfort, aching, or heaviness
  • redness of the face, neck, arms, and occasionally, upper chest
  • redness, swelling, or tenderness at the injection site
  • runny or stuffy nose
  • skin lesions
  • sneezing
  • sore throat
  • speech problems
  • swelling of the face, lips, or eyelids
  • troubled breathing
  • Earache
  • general feeling of discomfort or illness
  • loss of appetite
  • painful blisters on trunk of the body
  • painful cold sores or blisters on the lips, nose, eyes, or genitals
Incidence not known:
  • Bleeding gums
  • blood in the urine or stools
  • bloody nose
  • chest discomfort
  • confusion
  • constipation
  • dark urine
  • decreased urine output
  • depressed mood
  • dilated neck veins
  • dry skin and hair
  • extreme fatigue
  • fast, irregular, or pounding heartbeat
  • feeling cold
  • general tiredness and weakness
  • hair loss
  • heavier menstrual periods
  • high fever
  • irregular breathing
  • light-colored stools
  • loss of bladder control
  • mental depression
  • mood or other mental changes
  • muscle cramps and stiffness
  • nausea or vomiting
  • nervousness
  • pale skin
  • persistent loss of appetite
  • pinpoint red spots on the skin
  • puffiness or swelling of the eyelids, or around the eyes, face, lips, or tongue
  • redness, blistering, peeling, or loosening of the skin
  • sensitivity to heat
  • skin rash
  • slowed heartbeat
  • sudden loss of consciousness
  • sweating
  • swelling of the face, fingers, feet, or lower legs
  • swelling of the mouth or throat
  • tightness in the chest
  • tightness in the throat
  • upper right abdominal or stomach pain or tenderness
  • weight gain or loss
  • yellow eyes and skin

Minor Side Effects

Some interferon beta-1a 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:
  • Heartburn
  • indigestion
  • sour stomach
Less common:
  • Hair loss
  • trouble sleeping

For Healthcare Professionals

Applies to interferon beta-1a: intramuscular kit, intramuscular powder for injection, subcutaneous kit, subcutaneous solution


Influenza-like symptoms (e.g., myalgia, fever, chills, sweating, asthenia, headache, nausea) are the most common adverse reactions.[Ref]


Very common (10% or more): Lymphopenia (14%), leukopenia (11%), neutropenia, thrombocytopenia, anemia
Common (1% to 10%): Neutrophil count decreased, hematocrit decreased, blood potassium increased, blood urea nitrogen increased
Uncommon (0.1% to 1%): Platelet count decreased
Rare (Less than 0.1%): Thrombotic microangiopathy including thrombotic thrombocytopenic purpura/hemolytic uremic syndrome,
Frequency not reported: Pancytopenia[Ref]


Very common (10% or more): Nausea (27%), diarrhea (17%), constipation (12%), vomiting (10%)
Common (1% to 10%): Abdominal pain, toothache
Frequency not reported: Dry mouth, dyspepsia[Ref]


Very common (10% or more): Skin rashes (25%), increased sweating
Common (1% to 10%): Contusion, pruritus, erythematous rash, maculopapular rash, night sweats
Uncommon (0.1% to 1%): Alopecia, allergic dermatitis, erythema, urticaria
Rare (0.01% to 0.1%): Skin ulceration/necrosis at the site of injection, Quincke's edema (angioedema), erythema multiforme, Stevens-Johnson syndrome
Very rare (less than 0.01%): Calcified subcutaneous nodules, psoriasis, periungual and nail alterations
Frequency not reported: Rash vesicular[Ref]


Uncommon (0.1% to 1%): Hypothyroidism, hyperthyroidism[Ref]


Frequency not reported: Cardiomyopathy, congestive heart failure, palpitations, arrhythmia, tachycardia, vasodilatation, chest pain, pulmonary arterial hypertension (PAH) (sometimes reported up to several years after starting treatment)[Ref]


Very common (10% or more): Urinary tract infection (19%), cystitis (11%)
Frequency not reported: Metrorrhagia, menorrhagia, urinary incontinence, increase in the frequency of micturition[Ref]


Very common (10% or more): Alanine aminotransferase increased (26%), aspartate aminotransferase increased (16%)
Common (1% to 10%): Gamma-glutamyl-transferase increased
Uncommon (0.1% to 1%): Hepatitis (with or without icterus)
Rare (Less than 0.1%): Hepatic failure, autoimmune hepatitis
Frequency not reported: Elevation of hepatic transaminases (SGPT and SGOT), bilirubinemia, jaundice[Ref]


Rare (Less than 0.1%): Anaphylactic reactions
Frequency not reported: Other allergic reactions[Ref]


Very common (10% or more): Influenza-like symptoms (49%)
Frequency not reported: Systemic lupus erythematosus, anaphylactic reaction, anaphylactic shock, hypersensitivity reactions (angioedema, dyspnea, urticaria, rash, pruritic rash)[Ref]


Very common (10% or more): Injection site erythema (62%), injection site pain (15%), injection site pruritus (13%), injection site bruising
Common (1% to 10%): Injection site edema, injection site warmth, injection site hematoma, injection site rash
Uncommon (0.1% to 1%): Injection site infections (which could be severe)
Rare (Less than 0.1%): Injection site cellulitis (which could be severe)
Frequency not reported: Injection site abscess, injection site reaction, injection site inflammation, injection site necrosis, injection site bleeding[Ref]


Very common (10% or more): Myalgia (19%), back pain (20%), pain in extremity (19%), arthralgia (16%), muscular weakness (12%), muscle spasms (10%)
Common (1% to 10%): Muscle spasticity, muscle cramp, neck pain, arthralgia, muscle stiffness, musculoskeletal stiffness
Rare (0.01% to 0.1%): Drug induced lupus erythematosus
Frequency not reported: Arthritis[Ref]

Nervous system

Very common (10% or more): Headache (67%), dizziness (16%), paresthesia (12%)
Common (1% to 10%): Hypoesthesia
Uncommon (0.1% to 1%): Facial hypoesthesia
Frequency not reported: Neurological symptoms, syncope, hypertonia, seizures, migraine[Ref]


Frequency not reported: Weight decreased, weight increased[Ref]


Common (1% to 10%): Eye pain
Uncommon (0.1% to 1%): Retinal vascular disorders (i.e. retinopathy, cotton wool spots, obstruction of retinal artery or vein)
Frequency not reported: Eye disorder, abnormal vision, xerophthalmia[Ref]


Very common (10% or more): Pyrexia (45%), asthenia (24%), pain (23%), fever (20%), chills (19%)
Common (1% to 10%): Fatigue, malaise, hyperthermia, vertigo
Frequency not reported: Tachyphylaxis, sudden hearing loss, tinnitus (ototoxic effects resolved 7 to 14 days after discontinuation of the drug)[Ref]


Common (1% to 10%): Depression/suicidal ideation, insomnia, somnolence
Uncommon (0.1% to 1%): Anxiety
Frequency not reported: Suicide attempt, suicide, psychosis, anxiety, confusion, emotional lability, anhedonia, psychotic thoughts, mood disturbances, hypersexuality, aggressive behavior, panic attacks[Ref]


Very common (10% or more): Oropharyngeal pain (28%), nasopharyngitis (24%), upper respiratory tract infection (21%), cough (16%), sinusitis (14%)
Common (1% to 10%): Rhinorrhea, bronchitis
Rare (0.01% to 0.1%): Dyspnea
Frequency not reported: Pulmonary arterial hypertension[Ref]


Rare (Less than 0.1%): Nephrotic syndrome, glomerulosclerosis[Ref]


1. "Product Information. Rebif (interferon beta-1a)." Serono Laboratories Inc, Norwell, MA.

2. "Product Information. Avonex (interferon beta-1a)." Biogen, Cambridge, MA.

3. Cerner Multum, Inc. "Australian Product Information." O 0

4. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

It is possible that some side effects of Rebif 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.