Intravenous immunoglobulin (IVIg) is a medical treatment that contains antibodies, which are proteins that help protect against infection. Doctors can use IVIg to treat immunodeficiencies, autoimmune diseases, or inflammatory diseases.

IVIg comes from plasma, which is a component of blood. Severe side effects from the treatment are rare, but milder ones may include a headache and feeling cold.

This article discusses the uses, side effects, risks, and results of IVIg. It also explains what happens during treatment and alternatives for those who cannot undergo IVIg treatment.

Close-up of an IV bag containing IVIg in a hospital room.Share on Pinterest
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Immunoglobulins are antibodies, which are proteins the body makes to protect itself against infections. They are part of the immune system and present in plasma, which is an amber-colored liquid that comes from blood.

Doctors can use immunoglobulins as a treatment therapy in the form of IVIg. To make it, a laboratory separates plasma from the blood of thousands of healthy donors and then combines it, creating a concentrate. Doctors then administer this concentrate intravenously, which means into a person’s veins.

There are several classes of immunoglobulins. The most abundant in human blood, and in IVIg, is immunoglobulin G (IVG). The composition of IVIg is very similar to the naturally occurring immunoglobulins in blood plasma, with IVG comprising more than 90% of the concentrate.

The potential uses for IVIg include:

  • Replacement therapy: Some people have health conditions that lower their antibody levels, such as immune deficiencies. Low dose IVIg can replace the missing antibodies and protect against a range of infections.
  • Hyperimmune therapy: Unlike replacement therapy, hyperimmune therapy protects against specific infections. It involves using plasma from donors who have recently received a vaccination, or who have recently recovered from an infectious disease. Doctors may use this approach to protect a person against a pathogen they have become exposed to, such as:
  • Inflammatory and autoimmune conditions: High doses of IVIg can decrease inflammation. They can also help block the immune system from attacking a person’s own cells, which is what happens in autoimmune diseases. Doctors may use IVIg to treat:

IVIg treatment can take place in a hospital or an outpatient setting, such as an infusion center or doctor’s office. Here is what to expect during the procedure:

  1. A healthcare professional will locate a vein and clean the skin.
  2. Next, they will insert an IV catheter into the arm, which may hurt temporarily. They will then begin the administration of the IVIg using the IV catheter.
  3. The person receiving treatment keeps the IV line in until the infusion is complete. This generally takes 3 hours. People can bring something to do, such as a book to read, to the appointment. The infusion process generally does not hurt.
  4. Once the infusion is complete, a healthcare professional will remove the IV catheter and place a dressing on the broken skin.

A person should arrange their transport home in advance, so that they do not have to drive after the appointment. Intervals between infusions may vary from days to weeks.

Side effects are possible during and after any IV infusion. Severe side effects are rare, according to the American Academy of Allergy, Asthma & Immunology, but milder ones may include:

  • a headache
  • feeling cold
  • muscle aches, tiredness, and fever for a day afterward

Rarer side effects may occur up to 72 hours following an infusion, according to the Immune Deficiency Foundation. These include:

  • aseptic meningitis, which is inflammation of the membrane that covers the brain and spinal cord
  • acute kidney failure, which is more likely to occur in people with kidney disease or who are older than age 65
  • anaphylaxis, which is a life threatening allergic reaction
  • hemolytic anemia, which is when the body destroys red blood cells faster than the body can replace them
  • blood clots, which are more likely to occur in those with heart disease, high blood pressure, or clotting disorders

The effectiveness of IVIg and the duration of its benefits varies from case to case.

Immunodeficiencies

Replacement therapy for people with low antibodies can prevent infections. People receiving IVIg for this purpose will probably need to have lifelong IVIg treatments, but IVIg is one of the most successful treatments for immunodeficiencies.

Autoimmune and inflammatory conditions

IVIg treats a variety of autoimmune and inflammatory conditions, so the results can vary.

A small 2022 study found that IVIg treatment improved symptoms of autoimmune encephalitis by the 8th day of the trial.

Another small study involving people with autoimmune dysautonomia also found favorable results – after 1 year of treatment, 74% of the 38 participants were almost able to return to work or school.

Some conditions may take longer to respond to IVIg than others. Researchers are still continuing to learn about how effective it is for different autoimmune and inflammatory disorders.

Some people may not want to take IVIg or may be unable to take it. A 2020 review indicates that new medications may show promise as IVIg alternatives for those with autoimmune or inflammatory conditions. These promising alternatives include:

  • Neonatal crystallizable fragment receptor inhibition: This is an agent that lowers IgG levels for the potential treatment of autoimmune conditions.
  • Complement inhibition: This includes agents that prevent a part of the immune system from damaging healthy cells.
  • Sialylated IgG: This may stop the development of some autoimmune conditions.

For people with immunodeficiencies, subcutaneous immunoglobulin (SCIg) may be a suitable alternative. This involves injecting purified immunoglobulin into the fatty tissue just beneath the skin, such as in the buttocks or thighs.

This option tends to cause fewer systemic side effects in comparison to IVIg, but those who have had severe reactions to IVIg may also react to SCIg.

After having IVIG, a person should talk with their doctor immediately if they experience persistent or severe headaches with:

  • neck stiffness
  • nausea
  • vomiting

For any other sudden or severe side effects, get medical attention immediately by dialing 911.

Anaphylaxis is a severe allergic reaction that can be life threatening. The symptoms develop suddenly and include:

  • hives
  • swelling of the face or mouth
  • wheezing
  • fast, shallow breathing
  • a fast heart rate
  • clammy skin
  • anxiety or confusion
  • dizziness
  • vomiting
  • blue or white lips
  • fainting or loss of consciousness

If someone has these symptoms:

  1. Check whether they are carrying an epinephrine pen. If they are, follow the instructions on the side of the pen to use it.
  2. Dial 911 or the number of the nearest emergency department.
  3. Lay the person down from a standing position. If they have vomited, turn them onto their side.
  4. Stay with them until the emergency services arrive.

Some people may need more than one epinephrine injection. If the symptoms do not improve in 5–15 minutes, or they come back, use a second pen if the person has one.

IVIg involves infusing a concentrate of antibodies into a vein. Low doses may help a person with an immunodeficiency to build an immune response against infections, while high doses may help relieve an inflammatory or autoimmune condition.

The infusion may take about 3 hours, and it generally does not cause pain. Depending on a person’s condition, they may need infusions throughout their life.

IVIg is generally safe, and any side effects are usually not serious.

However, in rare cases, IVIg can cause complications up to 72 hours after the procedure, such as blood clots or an anaphylactic reaction. If a person already has a high risk of these conditions, they should discuss the potential benefits and risks with a doctor.