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PLEGRIDY safety and side effects

Understanding PLEGRIDY safety and potential side effects

It is important to talk to your healthcare provider about the potential side effects of PLEGRIDY.

PLEGRIDY can cause serious side effects, including:

Liver problems, or worsening of liver problems, including liver failure and death. Symptoms may include yellowing of your skin or the white part of your eye, nausea, loss of appetite, tiredness, bleeding more easily than normal, confusion, sleepiness, dark colored urine, and pale stools. During your treatment with PLEGRIDY you will need to see your healthcare provider regularly. You will have regular blood tests to check for these possible side effects.

Depression or suicidal thoughts. Symptoms may include new or worsening depression (feeling hopeless or bad about yourself), thoughts of hurting yourself or suicide, irritability (getting upset easily), nervousness, or new or worsening anxiety.

Call your healthcare provider right away if you have any of the symptoms listed above. 

PLEGRIDY may cause additional serious side effects, including:

Serious allergic reactions. Serious allergic reactions can happen if you take PLEGRIDY. Symptoms may include itching, swelling of the face, eyes, lips, tongue, or throat, trouble breathing, feeling faint, anxiousness, skin rash, hives, or skin bumps. Get emergency help right away if you have any of these symptoms. Talk to your healthcare provider before taking another dose of PLEGRIDY.

Injection site reactions. PLEGRIDY may commonly cause redness, pain, itching or swelling at the place where the injection was given. Call your healthcare provider right away if an injection site becomes swollen and painful or the area looks infected. You may have a skin infection or an area of severe skin damage (necrosis) requiring treatment by a healthcare provider.

Heart problems, including congestive heart failure. Call your healthcare provider right away if you have worsening symptoms of heart failure such as shortness of breath or swelling of your lower legs or feet while using PLEGRIDY.

  • Some people using PLEGRIDY may have other heart problems, including low blood pressure, fast or abnormal heartbeat, chest pain, heart attack, or a heart muscle problem (cardiomyopathy)

Blood problems and changes in your blood tests. PLEGRIDY can decrease your white blood cells or platelets, which can cause an increased risk of infection, bleeding, or anemia and can cause changes in your liver function tests. Your healthcare provider will do tests to monitor for side effects while you use PLEGRIDY.

Thrombotic microangiopathy (TMA). TMA is a condition that involves injury to the smallest blood vessels in your body. TMA can also cause injury to your red blood cells (the cells that carry oxygen to your organs and tissues) and your platelets (cells that help your blood clot) and can sometimes lead to death. Your healthcare provider may tell you to stop taking PLEGRIDY if you develop TMA.

Pulmonary arterial hypertension. Pulmonary arterial hypertension can occur with interferon beta products, including PLEGRIDY. Symptoms may include new or increasing fatigue or shortness of breath. Contact your healthcare provider right away if you develop these symptoms.

Autoimmune diseases. Problems with easy bleeding or bruising (idiopathic thrombocytopenia), thyroid gland problems (hyperthyroidism and hypothyroidism), and autoimmune hepatitis have happened in some people who use interferon beta.

Seizures. Some people have had seizures while taking PLEGRIDY, including people who have never had seizures before.

Tell your healthcare provider right away if you have any of the symptoms listed above.

These are not all of the possible side effects of PLEGRIDY.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Understanding the most common side effects of PLEGRIDY

In a 1-year study of subcutaneous PLEGRIDY, the most common side effects experienced by ≥10% of people taking PLEGRIDY and at least 2% more than placebo were redness around the injection site, flu-like symptoms, fever, headache, muscle pain, chills, injection site pain, weakness or loss of strength, itching at the injection site, and joint pain.

Injection site reactions

You may experience injection site reactions with PLEGRIDY. Symptoms include redness, pain, itching, or swelling at the place where your injection was given.

  • In clinical studies of subcutaneous PLEGRIDY, injection site reactions occurred in 66% of people taking PLEGRIDY, compared with 11% of those taking placebo
    • Severe injection site reactions occurred in 3% of the PLEGRIDY group and 0% of the placebo group
    • 1 out of 1468 people who took PLEGRIDY experienced injection site necrosis. Necrosis is a skin infection or area of severe skin damage that would require treatment by your healthcare provider
  • In a separate clinical study comparing intramuscular and subcutaneous PLEGRIDY in 130 healthy volunteers, injection site reactions occurred in 14% of people taking intramuscular PLEGRIDY and 32% of people taking subcutaneous PLEGRIDY
Flu-like symptoms

Many people who use PLEGRIDY have flu-like symptoms, especially early in the course of therapy. These symptoms are not really the flu. You cannot pass it on to anyone else. Flu-like symptoms may include headache, muscle and joint aches, fever, chills, or tiredness.

  • In a 1-year study of subcutaneous PLEGRIDY, 47% of people taking PLEGRIDY experienced flu-like symptoms, compared with 13% of people taking placebo
  • Fewer than 1% of people taking PLEGRIDY stopped treatment due to flu-like symptoms

See tips for managing flu-like symptoms and injection site reactions

These are not all of the possible side effects of PLEGRIDY.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

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Managing common side effects

Find tips to help manage flu-like symptoms and injection site reactions.
Check out the tips