Pegasys Side Effects

Generic name: peginterferon alfa-2a

Note: This document contains side effect information about peginterferon alfa-2a. Some of the dosage forms listed on this page may not apply to the brand name Pegasys.

Some side effects of Pegasys may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

For the Consumer

Applies to peginterferon alfa-2a: subcutaneous kit, subcutaneous solution

Get emergency medical help if you have any of these signs of an allergic reaction while taking peginterferon alfa-2a (the active ingredient contained in Pegasys) hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop using this medication and call your doctor at once if you have a serious side effect such as:

• confusion, severe depression, thoughts of hurting yourself or others;

• unusual thoughts or behaviors, feeling anxious or aggressive;

• sudden weakness, loss of balance or coordination, or problems with speech;

• chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, general ill feeling;

• numbness, burning, pain, or tingly feeling;

• fever, chills, body aches, flu symptoms;

• easy bruising or bleeding, feeling very tired;

• sores in your mouth, nose or eyes;

• redness, crusting, or drainage in your eyes;

• worsening of psoriasis;

• cough, stabbing chest pain, feeling short of breath;

• severe pain in your upper stomach spreading to your back, fast heart rate;

• high blood sugar (increased thirst, increased urination, hunger, dry mouth, fruity breath odor, drowsiness, dry skin, blurred vision, weight loss);

• low blood sugar (headache, hunger, weakness, sweating, tremors, irritability, trouble concentrating);

• vision changes, headache or pain behind your eyes; or

• fever with severe stomach pain and bloody diarrhea.

Less serious side effects of peginterferon alfa-2a may include:

• vomiting, upset stomach, loss of appetite, mild diarrhea;

• weight changes, feeling very hot or cold;

• headache, muscle or joint pain;

• sleep problems (insomnia);

• temporary hair loss, mild skin rash; or

• itching, redness, dryness, or swelling where the medicine was injected.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.

For Healthcare Professionals

Applies to peginterferon alfa-2a: subcutaneous kit, subcutaneous solution

General

During hepatitis C studies, one or more serious side effects were reported in 10% of chronic hepatitis C (CHC) patients and 19% of CHC patients coinfected with HIV. The most common serious side effect was bacterial infection, including sepsis, osteomyelitis, endocarditis, pyelonephritis, and pneumonia (3% CHC, 5% CHC/HIV). Other serious side effects have included suicide, suicidal ideation, psychosis, aggression, anxiety, drug abuse and drug overdose, angina, hepatic dysfunction, fatty liver, cholangitis, arrhythmia, diabetes mellitus, autoimmune phenomena (e.g., hyperthyroidism, hypothyroidism, sarcoidosis, systemic lupus erythematosus, rheumatoid arthritis), peripheral neuropathy, aplastic anemia, peptic ulcer, gastrointestinal bleeding, pancreatitis, colitis, corneal ulcer, pulmonary embolism, coma, myositis, cerebral hemorrhage, thrombotic thrombocytopenic purpura, psychotic disorder, and hallucination in less than 1% of patients.

The most common side effects have included psychiatric reactions (including depression, insomnia, irritability, anxiety), influenza-like symptoms (such as fatigue, pyrexia, myalgia, headache, rigors), anorexia, nausea and vomiting, diarrhea, arthralgias, injection site reactions, alopecia, and pruritus. Psychiatric disorders, influenza-like syndrome (e.g., lethargy, fatigue, headache), dermatologic disorders, gastrointestinal disorders, and laboratory abnormalities (thrombocytopenia, neutropenia, anemia) were the most common reasons for discontinuation of therapy.

Immunologic

Frequency not reported: Bacterial infections (e.g., sepsis, osteomyelitis, endocarditis, pyelonephritis, pneumonia), infections (appendicitis, tuberculosis, influenza), autoimmune phenomena (e.g., hyperthyroidism, hypothyroidism, sarcoidosis, systemic lupus erythematosus, rheumatoid arthritis), development of binding antibodies to peginterferon alfa-2a (the active ingredient contained in Pegasys) Alpha interferons: Development or exacerbation of autoimmune disorders (including myositis, hepatitis, thrombotic thrombocytopenic purpura, idiopathic thrombocytopenic purpura, psoriasis, rheumatoid arthritis, interstitial nephritis, thyroiditis, systemic lupus erythematosus)
Postmarketing reports: Liver graft rejection, renal graft rejection

The most common or important serious side effects reported during hepatitis B studies have included infections (sepsis, appendicitis, tuberculosis, influenza).

Liver graft rejection and renal graft rejection have been reported with peginterferon alfa-2a alone or in combination with ribavirin.

Hematologic

Neutropenia (40%), anemia (14%), and thrombocytopenia (8%) have been reported during treatment with peginterferon alfa-2a (the active ingredient contained in Pegasys) plus ribavirin in CHC patients coinfected with HIV.

Laboratory abnormalities (thrombocytopenia, neutropenia, and anemia) were among the most common reasons given for discontinuation of therapy.

The most common or important serious side effects reported during hepatitis B studies have included thrombotic thrombocytopenic purpura.

Pure red cell aplasia has been reported with peginterferon alfa-2a alone or in combination with ribavirin.

Very common (10% or more): Neutropenia (21% monotherapy, 27% to 40% combination therapy), lymphopenia (14% combination therapy), anemia (11% to 14% combination therapy)
Common (1% to 10%): Thrombocytopenia (5% monotherapy, 5% to 8% combination therapy), lymphopenia (3% monotherapy), anemia (2% monotherapy)
Frequency not reported: Aplastic anemia, thrombotic thrombocytopenic purpura, cerebral hemorrhage
Postmarketing reports: Pure red cell aplasia

Hepatic

Common (1% to 10%): Hepatic decompensation (2%)
Frequency not reported: Elevated ALT (occasionally associated with hyperbilirubinemia), hepatic dysfunction, fatty liver, cholangitis, exacerbations of hepatitis, hepatitis B flares

Hepatic decompensation has been reported in 2% of CHC patients coinfected with HIV.

The most common or important serious side effects reported during hepatitis B studies have included hepatitis B flares.

Other

Fatigue has been reported in 24% of patients during hepatitis B studies.

Sarcoidosis has been reported in a 65-year-old man at the seventh month of therapy. Most of the symptoms improved over the next three months following discontinuation of therapy.

Very common (10% or more): Influenza-like signs and symptoms: Fatigue/asthenia (56% monotherapy, 65% combination therapy), pyrexia (37% to 54% monotherapy, 41% combination therapy), rigors (35% monotherapy, 25% combination therapy), pain (11% monotherapy, 10% combination therapy); fatigue (24%); overall resistance mechanism disorders (10% monotherapy, 12% combination therapy)
Common (1% to 10%): Fever, chills
Rare (less than 0.1%): Mucosal hyperpigmentation, sarcoidosis (at least 1 case)

Nervous system

Very common (10% or more): Headache (27% to 54% monotherapy, 43% combination therapy), insomnia (19% monotherapy, 30% combination therapy), dizziness (excluding vertigo; 16% monotherapy, 14% combination therapy)
Common (1% to 10%): Concentration impairment (8%), memory impairment (5% monotherapy, 5% combination therapy)
Rare (less than 0.1%): Chorea and akathisia (at least 1 case)
Frequency not reported: Peripheral neuropathy, hallucination, coma
Postmarketing reports: Seizures, hearing impairment, hearing loss

A 40-year-old male coinfected with hepatitis C virus and HIV experienced chorea and akathisia coincident with peginterferon alfa-2a therapy. He was administered subcutaneous peginterferon alfa-2a 180 mcg weekly and oral ribavirin 1 g daily. At week 20 of therapy, the patient presented to the clinic complaining of irritability, difficulty in sleeping and prominent choreiform involuntary movements with myoclonic activity of the upper and lower extremities. He was diagnosed with chorea and akathisia. He was treated with ropinirole, propranolol, and clonazepam. Peginterferon alfa-2a and ribavirin were discontinued with complete resolution of symptoms after 5 days.

Musculoskeletal

Very common (10% or more): Myalgia (26% to 37% monotherapy, 40% combination therapy), arthralgia (28% monotherapy, 22% combination therapy)
Common (1% to 10%): Back pain (9% monotherapy, 5% combination therapy)
Frequency not reported: Myositis

Psychiatric

Very common (10% or more): Irritability/anxiety/nervousness (19% monotherapy, 33% combination therapy), depression (18% monotherapy, 20% combination therapy), concentration impairment (10% combination therapy)
Common (1% to 10%): Concentration impairment (8% monotherapy), mood alteration (3% monotherapy, 5% combination therapy)
Frequency not reported: Suicidal ideation, suicide, psychosis, aggression, psychotic disorder, relapse of drug abuse, drug overdose, impairment of desire, sexual satisfaction affected (potentially), sexual dysfunction

Psychiatric side effects were among the most common reasons given for discontinuation of therapy.

Impairment of desire, sexual satisfaction affected (potentially), and sexual dysfunction have been reported with peginterferon alfa-2a plus ribavirin in male patients.

Dermatologic

Very common (10% or more): Alopecia (18% to 23% monotherapy, 28% combination therapy), pruritus (12% monotherapy, 19% combination therapy), dermatitis (16% combination therapy), dry skin (10% combination therapy)
Common (1% to 10%): Dermatitis (8% monotherapy), increased sweating (6% monotherapy, 6% combination therapy), rash (5% monotherapy, 8% combination therapy), dry skin (4% monotherapy), eczema (1% monotherapy, 5% combination therapy)
Rare (less than 0.1%): Drug-induced Sweet's syndrome (at least 1 case)
Frequency not reported: Lichenoid eruptions, maculopapular rashes
Postmarketing reports: Serious skin reactions

Dermatologic side effects were among the most common reasons given for discontinuation of therapy.

Skin disorders associated with combination therapy have included lichenoid eruptions and maculopapular rashes.

Gastrointestinal

Very common (10% or more): Nausea and vomiting (24% monotherapy, 25% combination therapy), diarrhea (16% monotherapy, 11% combination therapy), abdominal pain (15% monotherapy)
Common (1% to 10%): Abdominal pain (8% combination therapy), dry mouth (6% monotherapy, 4% combination therapy), dyspepsia (6% combination therapy)
Uncommon (0.1% to 1%): Dyspepsia (less than 1% monotherapy)
Rare (less than 0.1%): Tongue hyperpigmentation
Frequency not reported: Peptic ulcer, gastrointestinal bleeding, pancreatitis, colitis

Gastrointestinal side effects were among the most common reasons given for discontinuation of therapy.

Metabolic

Elevated triglyceride levels have been reported in patients receiving alfa interferons, including peginterferon alfa-2a (the active ingredient contained in Pegasys)

Very common (10% or more): Anorexia (16% to 17% monotherapy, 24% combination therapy), weight decrease (10% combination therapy)
Common (1% to 10%): Weight decrease (4% monotherapy)
Frequency not reported: Elevated triglycerides, diabetes mellitus
Postmarketing reports: Dehydration

Local

Very common (10% or more): Injection site reactions (22% monotherapy, 23% combination therapy)
Frequency not reported: Cutaneous necrosis at injection sites, hyperpigmentation around/over injection sites

Skin disorders associated with combination therapy have included cutaneous necrosis at peginterferon alfa-2a injection sites.

Hypersensitivity

Anaphylactic shock has been reported during hepatitis B studies.

Frequency not reported: Anaphylactic shock

Respiratory

Very common (10% or more): Dyspnea (13% combination therapy), cough (10% combination therapy)
Common (1% to 10%): Dyspnea (4% monotherapy), cough (4% monotherapy), exertional dyspnea (4% combination therapy)
Uncommon (0.1% to 1%): Exertional dyspnea (less than 1% monotherapy)
Frequency not reported: Pneumonia, interstitial pneumonitis, pulmonary embolism

Cardiovascular

Frequency not reported: Angina, arrhythmia, endocarditis

Ocular

Common (1% to 10%): Blurred vision (4% monotherapy, 5% combination therapy)
Frequency not reported: Corneal ulcers
Postmarketing reports: Serous retinal detachment

Endocrine

Common (1% to 10%): Hypothyroidism (3% monotherapy, 4% combination therapy)
Frequency not reported: Hyperthyroidism

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 information does not endorse drugs, diagnose patients, or recommend therapy. This drug 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 drug combination in no way should be construed to indicate that the drug of drug combination is safe, effective, or appropriate for any given patient. Drugs.com does not assume any responsibility for any aspect of healthcare administered with the aid of information 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 drugs you are taking, check with your doctor, nurse, or pharmacist.