Many treatments for myasthenia gravis (MG) help manage symptoms by calming the immune system’s attack on the body. Intravenous immunoglobulin (IVIG) is one such therapy. IVIG can be used to reduce MG symptoms, along with thymectomy (surgical removal of the thymus gland), acetylcholinesterase inhibitors (which improve nerve-muscle communication), and immunosuppressants like corticosteroids.

Read on to find out how IVIG works, when it’s used, and the potential risks and benefits of this treatment of myasthenia gravis.

What Is IVIG?

Antibodies are proteins made by the immune system to help fight off infections like bacteria and viruses. But in autoimmune disorders like myasthenia gravis, the immune system mistakenly produces autoantibodies — proteins that attack the body’s own cells instead of harmful invaders.

In myasthenia gravis, these autoantibodies target receptors on nerve endings, where nerves communicate with muscles. This interference makes it harder for nerves to communicate with muscles, leading to symptoms like muscle weakness, diplopia (double vision), and fatigue (extreme tiredness that doesn’t improve with sleep).

Types of Immunoglobulin

“Immunoglobulin” is another term for “antibody.” There are five types of immunoglobulins, each with a unique role in fighting infections and maintaining immune function. The most common type is immunoglobulin G, which is the main component of IVIG therapy. IVIG also contains small amounts of immunoglobulin M and immunoglobulin A.

How Is IVIG Produced?

IVIG therapy uses concentrated antibodies collected from the blood of thousands of healthy donors. This process ensures a high level of immunoglobulin G, the main antibody used in treatment.

You might wonder whether IVIG could carry a risk of infection from donors. However, all donated blood goes through thorough screening for bacteria and viruses, and it’s carefully processed to remove any risk of transmitting infections.

How Does IVIG Work?

Doctors and researchers don’t fully understand why IVIG helps treat autoimmune conditions. One theory involves the neonatal Fc receptor (FcR). FcR is a protein that allows the immune system to control antibody levels in the immune system. FcR is also present in IVIG. Adding more FcR to the bloodstream may signal the body to get rid of extra antibodies — including autoantibodies, which are antibodies that mistakenly attack the body’s own cells and contribute to autoimmune diseases like MG.

Other Conditions for Which IVIG Is Used

IVIG therapy is sometimes used for other autoimmune diseases and inflammatory conditions caused by autoantibodies attacking healthy cells.

Conditions that may be treated with IVIG include:

• Autoimmune hemolytic anemia — A condition where the immune system destroys red blood cells
• Immune thrombocytopenia — A disorder in which platelets (cell fragments that help blood clot) are destroyed
• Guillain-Barré syndrome — A rare disorder where the immune system attacks the nerves, leading to weakness and paralysis

The Process of Receiving IVIG

IVIG treatment is given intravenously (through an IV), which means it’s infused directly into a vein. Because the infusion is slow and controlled, it must be done at a healthcare facility. There, healthcare providers will monitor your vital signs (like blood pressure and heart rate) and help manage any side effects.

How long IVIG takes and how often you need it will depend on your specific situation. When used to manage a myasthenia gravis flare, IVIG is usually used as a short-term treatment, lasting two to five days or given as one large dose. The amount of medication that you receive and how fast it’s delivered depends on your weight and how long you’ve been receiving treatment. It may take a few weeks before you notice symptom relief.

Although IVIG is most commonly given by IV, a subcutaneous form (injected under the skin) has been found to be an effective alternative for many autoimmune and immune deficiency conditions. Studies show that subcutaneous immunoglobulin can provide similar benefits to IVIG, with the added advantage of fewer serious side effects and the possibility of at-home administration. However, further studies are needed to determine the optimal use for subcutaneous immunoglobulin in myasthenia gravis.

Potential Benefits of IVIG for Myasthenia Gravis

IVIG is an effective short-term treatment for people with myasthenia gravis flares (periods of active symptoms). One study across 10 countries found that people treated with IVIG had clinically meaningful symptom improvement within two weeks, compared to those who didn’t receive it​.

IVIG can be especially helpful during a myasthenic crisis, a rapid and potentially life-threatening worsening of MG symptoms. However, its long-term role as a maintenance therapy remains uncertain, and more research is needed to determine its effectiveness for ongoing symptom management​.

Potential Risks and Side Effects of IVIG

Like all medications, IVIG has common side effects and rare but serious risks. In one study, about 80 percent of people experienced mild to moderate side effects.

Common Side Effects of IVIG

Some side effects that may occur during or shortly after an infusion may include:

• Headaches
• Rash
• Abdominal pain
• Fever
• Nausea and vomiting
• Joint and lower back pain

If these side effects are bothersome and occur while you’re getting the infusion, the treatment can be slowed or stopped.

Rare Side Effects of IVIG

A more serious side effect of IVIG is an allergic reaction to the treatment itself. Symptoms of an allergic reaction include:

• Itchy skin with hives
• Swelling of the face and tongue
• Lightheadedness
• Difficulty breathing

Healthcare providers closely monitor for allergic reactions and are prepared to treat them if they occur.

More rare, serious side effects may include:

• Kidney failure
• Liver problems
• Brain inflammation
• Anemia (low levels of red blood cells)
• Stroke
• Heart attack
• Blood clots

Vaccines and IVIG

IVIG can reduce the effectiveness of vaccines, so it’s generally recommended to wait at least six weeks before getting vaccinated. This waiting period may change depending on what type of vaccine you’ll be receiving. Talk to your doctor if you have concerns about timing vaccines around IVIG.

Read more about vaccinations and MG.

Avoiding IVIG Risks

Doctors and transfusion staff take many steps to reduce the risk of side effects during IVIG infusions, including:

• Testing your blood before and after your infusion — This helps to monitor for any changes in kidney function or other concerns.
• Encouraging hydration — Drinking plenty of fluids before your infusion can help, and IV fluids may be given during treatment if needed.
• Adjusting the infusion rate — If you experience side effects, the infusion may be slowed or paused to ease discomfort.
• Providing supportive medications — Over-the-counter medications, like pain relievers or antihistamines, may help reduce common side effects.
• Monitoring for allergic reactions — Healthcare providers watch closely for any serious side effects, like swelling, hives, or difficulty breathing, and are prepared to treat them immediately.

If IVIG is part of your MG treatment plan and you have questions about its effectiveness or safety, talk to your doctor. They can discuss how IVIG may help manage your symptoms and inform you about new treatment options as they become available.

Talk With Others Who Understand

On MGteam, the social network for people living with myasthenia gravis and their loved ones, members come together to ask questions, give advice, and share their stories with others who understand life with myasthenia gravis.

Have you used IVIG to treat your myasthenia gravis? Did you experience benefits or side effects? Share your story in the comments below, or start a conversation by posting on your Activities page.