PEGASYS Side Effects by Likelihood and Severity

COMMON side effects

If experienced, these tend to have a Severe expression i

  • low levels of a type of white blood cell called neutrophils
  • depression
  • fever

If experienced, these tend to have a Less Severe expression i

  • dry mouth
  • inflammation of the skin due to an allergy
  • itching
  • hair loss
  • joint pain
  • backache
  • muscle pain
  • difficulty concentrating
  • dizziness
  • difficulty sleeping
  • low energy
  • flu-like symptoms
  • pain
  • decreased appetite
  • headache
  • nausea
  • vomiting
  • diarrhea
  • stomach cramps
  • nervousness
  • reactions at the site of the injection
  • generalized weakness
  • irritability
  • anxious feelings

INFREQUENT side effects

If experienced, these tend to have a Severe expression i

  • a systemic inflammatory response called sepsis due to an infection with bacteria
  • a bacterial infection
  • a condition with low thyroid hormone levels
  • decreased blood platelets
  • a decreased number of lymphocytes in the blood
  • endocarditis, an infection of a heart valve
  • pneumonia
  • pyelonephritis, infection and inflammation of the kidney and renal pelvis
  • bone infection and inflammation

If experienced, these tend to have a Less Severe expression i

  • mood changes
  • blurred vision
  • a type of skin condition with redness and itching called eczema
  • dry skin
  • memory loss
  • excessive sweating
  • weight loss
  • trouble breathing
  • cough

RARE side effects

If experienced, these tend to have a Severe expression i

  • sarcoidosis
  • an infection
  • overactive thyroid gland
  • thyroid gland inflammation
  • diabetes
  • low blood sugar
  • dehydration
  • a type of blood disorder with a decrease in all types of blood cells called pancytopenia
  • low blood counts due to bone marrow failure
  • anemia
  • large purple or brown skin blotches
  • low platelet count and bleeding from immune response
  • mental problems from taking the drug
  • manic behavior
  • suicidal thoughts
  • thoughts of hurting or killing others
  • a painful condition that affects the nerves in the legs and arms called peripheral neuropathy
  • detachment of the retina of the eye
  • a disorder of the retina of the eye
  • a clot in the small veins that carry blood to or from the retina of the eye
  • vision loss
  • optic disk edema
  • sudden blindness and pain upon moving the eye
  • hearing loss
  • high blood pressure
  • a heart attack
  • a clot in the lung
  • pulmonary hypertension
  • abnormal heart rhythm
  • supraventricular arrhythmias, a type of abnormal heart rhythm
  • a hemorrhage in the brain
  • a stroke
  • thrombotic thrombocytopenic purpura, a type of blood disorder
  • a type of lung condition called bronchiolitis obliterans
  • a type of inflammation of the lung called interstitial pneumonitis
  • x-ray results showing lung tissue changes
  • bronchospasm
  • an ulcer from too much stomach acid
  • ulcerative colitis, an inflammatory condition of the intestines
  • inflammation of the large intestine
  • liver inflammation resulting from an abnormal immune response
  • enlarged fatty liver
  • cholangitis, an infection resulting from gallstones
  • a type of kidney inflammation called interstitial nephritis
  • a skin disorder with blistering and peeling skin called Stevens-Johnson syndrome
  • skin rash with sloughing
  • hives
  • systemic lupus erythematosus, an autoimmune disease
  • rheumatoid arthritis
  • an abscess
  • hallucinations
  • seizures
  • high blood sugar
  • abnormal liver function tests
  • a significant type of allergic reaction called anaphylaxis
  • a type of allergic reaction called angioedema
  • pancreatitis
  • macular edema
  • a blood clot in a retinal vein
  • pure red cell aplasia

If experienced, these tend to have a Less Severe expression i

  • angina, a type of chest pain
  • indigestion
  • chills

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Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, except as may be authorized by the applicable terms of use.

CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.