Prescription onlyClass: Autoimmune


(interferon beta-1b)

Prescription onlyClass: Autoimmune
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Lowers the frequency of MS exacerbations.

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Our bottom line

Betaseron (Interferon Beta-1B) is an injectable medicine effective for relapsing, remitting MS with fewer side effects and every other day dosing.

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  • Interferon beta-1b was the first disease modifying agent for MS approved by the FDA to treat relapsing-remitting multiple sclerosis (RRMS).
  • In short and long-term follow-up studies, Interferon beta-1b was shown to slow MS progression, reduce the number of flair-ups and increase overall survival.
  • Convenient every-other-day dosing and refrigeration-free storage (before mixing) is less of a hassle.
  • Interferon beta-1b has been shown to be more effective than Avonex in reducing new lesions, which lowers relapse and disease progression in people with RRMS.
  • May be a treatment option for people with secondary progressive multiple sclerosis (SPMS).
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  • Requires injections.
  • Injection site reactions are common. Symptoms range from pain, redness, and swelling to severe reactions with skin death around the injection site.
  • Flu-like symptoms are common after interferon injections, but are less likely with Interferon beta-1b in particular.
  • Blood testing required before and during use based on your other conditions.
  • Unclear consequences to fetus during pregnancy.
How it works

Betaseron (Interferon Beta-1B) is a man-made interferon that's similar to what your body naturally makes. Researchers don't know exactly how it works for MS, but interferons activate your own immune system to control immune responses that have gone out of control.

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Side effect rates for Betaseron (interferon beta-1b)

2372 From clinical trials of Betaseron / Multiple Sclerosis
  • Lymphocytes count decreased (<1500/mm3)
  • Muscle weakness
  • Immunogenicity
  • Headache
  • Flu-like symptoms (complex)
  • Pain
  • Stiff or rigid muscles
  • Injection site reaction
  • Fever
  • Low white blood cells

Risks and Warnings for Betaseron (interferon beta-1b)

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    • Higher risk if:
    • Alcohol use
    • Taking drugs that are liver toxic
    • Active or history of liver disease

    People taking Betaseron (Interferon Beta-1B) had liver injury and failure, some due to autoimmune hepatitis. There's a higher risk if you're taking medications or substances (e.g. alcohol) that hurt your liver. Talk to your doctor if you develop symptoms of nausea, vomiting, belly pain, tiredness, loss of appetite, or you notice yellowing of your skin/whites of eyes or dark urine, change in stool color, or skin rash. Betaseron (Interferon Beta-1B). Betaseron (Interferon Beta-1B) can cause elevated liver enzymes with no symptoms. If levels increase significantly, your doctor may lower your dose or stop Betaseron (Interferon Beta-1B) completely.

Common concerns from people taking Betaseron (interferon beta-1b)

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  • Interferon beta-1b has been shown to be more effective than Avonex in reducing new lesions, which lowers relapse and disease progression in people with RRMS.
  • Betaseron (Interferon Beta-1B) has been reported to cause hypersensitivity reactions (severe rash, trouble breathing) and rarely, angioedema (life-threatening condition with swelling with or without hives). If you develop these symptoms after your dose or days later, call your doctor and get medical emergency care right away.You may need to stop taking Betaseron (Interferon Beta-1B).
  • Betaseron (Interferon Beta-1B) may increase the risk of suicidal thoughts or behavior. Watch for new or worsening depression or any unusual changes in mood or behavior, especially during the first few months of treatment or when the dose changes. Tell your doctor right away if you have any of these symptoms.
  • Betaseron (Interferon Beta-1B) is not thought to cause adverse effects on the heart, but people taking it who didn't have heart problems developed heart failure and heart muscle weakness. Your doctor will do tests to check your heart function. Tell your doctor if you have ankle swelling, shortness of breath, rapid heartbeat, tightness in your chest or aren't able to lie flat in bed at night because you can't breathe.
  • People who start Betaseron (Interferon Beta-1B) report flu-like symptoms that include fever, chills, sweating, muscle aches and tiredness. Taking a pain reliever or fever reducer like Tylenol or a non-steroidal anti-inflammatory drug like Motrin may help. Be sure to ask your doctor first.
  • Betaseron (Interferon Beta-1B) can harm your unborn baby. There's also a risk you can lose your baby (miscarry). Tell your doctor right away if you become pregnant during treatment. You and your doctor should discuss if you should continue or stop taking Betaseron (Interferon Beta-1B).
  • Betaseron (Interferon Beta-1B) can lower the number of blood cells that help you fight infection and clot blood. White blood cells, red blood cells and platelets can all be affected. Tell your doctor if you feel tired, bruise easily or have any bleeding. you'll need to have blood tests to make sure they don't get too low.
  • Injection site reactions can be common, including swelling, redness, pain, and rarely death of surrounding skin tissues.
  • Injection site reactions can be severe and include pain, redness, swelling, and tissue death. In some cases they need surgical treatment and may not heal, causing scarring. Reactions happen in the first 4 months up to a year after starting and tend get better over time. don't inject into any area that’s not completely healed. If there are several areas, stop taking Betaseron (Interferon Beta-1B) until you have a chance to heal. It’s important that change your injection sites often, follow instructions carefully and learn how to inject it correctly.