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Extavia Side Effects

Generic Name: interferon beta-1b

Note: This page contains information about the side effects of interferon beta-1b. Some of the dosage forms included on this document may not apply to the brand name Extavia.

In Summary

Common side effects of Extavia include: uterine hemorrhage, chest pain, pain, abdominal pain, increased serum alanine aminotransferase, myalgia, fever, insomnia, headache, leukopenia, weakness, antibody development, decreased white blood cell count, injection site reaction, hypertonia, flu-like symptoms, anxiety, nausea, myasthenia, diarrhea, constipation, dyspepsia, arthralgia, skin rash, dizziness, lymphocytopenia, peripheral edema, urinary urgency, dermatological disease, chills, inflammation at injection site, and abnormal absolute neutrophil count. Other side effects include: lymphadenopathy, palpitations, tachycardia, hypertension, leg cramps, dyspnea, alopecia, tissue necrosis at injection site, urinary frequency, impotence, weight gain, nervousness, vasodilatation, peripheral vascular disease, malaise, and diaphoresis. See below for a comprehensive list of adverse effects.

For the Consumer

Applies to interferon beta-1b: subcutaneous powder for solution

In addition to its needed effects, some unwanted effects may be caused by interferon beta-1b (the active ingredient contained in Extavia). In the event that any of these side effects do occur, they may require medical attention.

Major Side Effects

You should check with your doctor immediately if any of these side effects occur when taking interferon beta-1b:

More common:
  • Abdominal or stomach pain
  • break in the skin at the injection site, with blue-black discoloration, swelling, or drainage of fluid
  • flu-like symptoms including chills, fever, generalized feeling of discomfort or illness, increased sweating, and muscle pain
  • headache or migraine
  • hives, itching, or swelling at the injection site
  • irregular or pounding heartbeat
  • redness, pain, or feeling of heat at the injection site
  • stuffy nose
Less common:
  • Breast pain
  • bloody or cloudy urine
  • changes in vision
  • cold hands and feet
  • difficult, burning, or painful urination
  • fast or racing heartbeat
  • frequent urge to urinate
  • pain
  • pelvic pain
  • swollen glands
  • troubled breathing
  • unusual weight gain
  • Abnormal growth in the breast
  • benign lumps in the breast
  • bleeding problems
  • bloating or swelling
  • changes in menstrual periods
  • confusion
  • convulsions (seizures)
  • cyst (abnormal growth filled with fluid or semisolid material)
  • decreased sexual ability in males
  • dry, puffy skin
  • feeling cold
  • hyperactivity
  • increased muscle tone
  • increased urge to urinate
  • loss of memory
  • mental depression with thoughts of suicide
  • problems with speaking
  • red, itching, or swollen eyes
  • swelling of the front part of the neck
  • unusual weight loss

Minor Side Effects

Some of the side effects that can occur with interferon beta-1b may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional:

More common:
  • Constipation
  • diarrhea
  • dizziness
  • loss of voice
  • menstrual pain or other changes
  • unusual tiredness or weakness
Less common:
  • Anxiety
  • drowsiness
  • hair loss
  • vomiting

For Healthcare Professionals

Applies to interferon beta-1b: subcutaneous powder for injection


Common (1% to 10%): Tachycardia
Rare (Less than 0.1%): Cardiomyopathy, congestive heart failure, palpitations, arrhythmia, tachycardia, vasodilatation, chest pain, hypertension[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]


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


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


Frequency not reported: Weight decreased, weight increased[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]


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]


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


1. Pharmaceutical Society of Australia "APPGuide online. Australian prescription products guide online. Available from: URL:" ([2006]):

2. "Product Information. Betaseron (interferon beta-1b)." Berlex, Richmond, CA.

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

Not all side effects for Extavia may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.

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.