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Compare Hepsera vs. Pegasys

Head-to-head comparisons of medication uses, side effects, warnings, and more.

Key takeaways

Adefovir (Hepsera) and peginterferon alfa-2a (Pegasys) are both used to treat hepatitis B, but they belong to different medication classes. Adefovir is a nucleoside reverse transcriptase inhibitor (NRTI) taken orally once a day, while Pegasys is an interferon alpha injected under the skin once a week. Adefovir is available as a generic, making it a lower-cost option, but it is not a first-choice treatment due to the risk of viral resistance. Pegasys is not recommended for hepatitis C treatment anymore and is only available as a brand name prefilled syringe for easier use. Common side effects of adefovir include weakness and headache, whereas Pegasys can cause flu-like symptoms, such as tiredness and fever. Pegasys also has more serious potential side effects, including mental health issues and autoimmune disorders. Both medications require regular monitoring, but Pegasys has more complex administration and storage requirements.

  • Adefovir (Hepsera)
    Pegasys (peginterferon alfa-2a)
  • Adefovir (Hepsera)
    Pegasys (peginterferon alfa-2a)

  • Summary of Hepsera vs. Pegasys

    Summary for Antiviral
    Prescription only

    Adefovir (Hepsera) is an antiviral medication that's used for the treatment of hepatitis B in people age 12 and older. It's not a first-choice treatment option because the virus can become resistant to adefovir (Hepsera), meaning the medication might stop working well over time. Adefovir (Hepsera) is available as a brand-name and generic tablet that's typically taken once daily. Some side effects of the medication can include weakness, headache, and stomach pain.

    Summary for Interferon alpha
    Prescription only

    Pegasys (peginterferon alfa-2a) is an interferon alpha. It's used to treat chronic (long-term) hepatitis B and hepatitis C in children and adults, sometimes in combination with other antivirals. Pegasys (peginterferon alfa-2a) is injected under the skin, typically once per week. The most common side effects of this medication include tiredness, headache, and fever.

  • Indications of Hepsera vs. Pegasys

    Indications for
    •Hepatitis B virus (HBV)
    Indications for
    •Long-term hepatitis C in people ages 5 years and older (in combination with other medications)
    •Long-term hepatitis B in people ages 3 years and older

  • Pros and Cons of Hepsera vs. Pegasys

    Pros and Const for Antiviral
    Pros
    •Only need to take once a day
    •Can take with or without food
    •Available as a lower-cost generic
    Cons
    •Not a first-choice medication to treat hepatitis B
    •High risk of viral resistance to the medication
    •Might cause buildup of lactic acid in the blood (lactic acidosis)
    Pros and Const for Interferon alpha
    Pros
    •Given only once per week
    •An option for children as young as 5 years old
    •Available as a prefilled syringe for easier use
    Cons
    •Can cause serious side effects, including mental health conditions and risk of serious infection
    •No longer recommended for hepatitis C treatment
    •Might be difficult for some people to administer correctly

  • Common Side Effects of Hepsera vs. Pegasys

    Common Side Effects for
    •Weakness or lack of energy (13%)
    •Headache (9%)
    •Stomach pain (9%)
    •Nausea (5%)
    Common Side Effects for

    Adults

    •Tiredness/fatigue (56%)
    •Headache (54%)
    •Muscle pain (37%)
    •Fever (37%)
    •Chills (35%)
    •Joint pain (28%)
    •Nausea/vomiting (24%)
    •Hair loss (23%)
    •Pain, swelling, or redness at injection site (22%)
    •Anxious/nervousness (19%)
    •Difficulty sleeping (19%)
    •Depression (18%)
    •Loss of appetite (17%)
    •Diarrhea (16%)
    •Dizziness (16%)
    •Stomach pain (15%)
    •Itching (12%)
    •Pain (11%)

    Children

    •Flu-like symptoms (fever, cough, short of breath) (81%)
    •Stomach problems (nausea, vomiting, diarrhea, stomach pain) (44%)
    •Pain, swelling, or redness at injection site (42%)
    •Headache (39%)
    •Muscle pain (29%)
    •Tiredness/weakness (20%)
    •Irritated/angry feeling (14%)
    •Itching (12%)
    •Difficulty sleeping (12%)
    •Rash (10%)

  • Warnings of Hepsera vs. Pegasys

    Common Side Effects for
    •Worsening of hepatitis B after stopping treatment
    •Hepatitis B and HIV co-infection
    •Kidney problems
    •Lactic acidosis and liver problems
    Common Side Effects for
    •Potential harm or death to your unborn baby
    •Mental health problems
    •Autoimmune disorders
    •Stroke or bleeding in the brain
    •Infections
    •Numbness or pain in your hands or feet (peripheral neuropathy)
    •Worsening liver problems and liver failure
    •Heart problems
    •Low blood cell counts
    •Hormone problems
    •Eye and vision problems
    •Lung problems
    •Intestine and pancreas problems
    •Delayed growth in children
    •Severe allergic and skin reactions

  • Prices with our coupons for Hepsera vs. Pegasys

    Learn more about Adefovir
    Learn more about Pegasys

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