Immunoglobulin Therapy: What It Is, How It Works, and What You Need to Know

When your body can’t make enough antibodies to fight off infections, immunoglobulin therapy, a treatment that provides ready-made antibodies from donated human blood. Also known as IVIG, it’s used to boost immunity in people with primary immune deficiencies, autoimmune disorders, and certain infections. Think of it like borrowing your body’s defense system from someone else’s blood—only it’s carefully screened, purified, and given in a controlled way so it actually works.

This treatment isn’t for everyone. It’s most common for people with primary immune deficiency, a group of disorders where the body doesn’t produce enough antibodies to protect against bacteria and viruses, like common variable immunodeficiency (CVID) or X-linked agammaglobulinemia. It’s also used in autoimmune conditions, where the immune system attacks the body’s own tissues, such as Guillain-Barré syndrome, chronic inflammatory demyelinating polyneuropathy (CIDP), and some cases of Kawasaki disease. The therapy works by flooding your bloodstream with antibodies that block harmful immune responses or help your body clear out pathogens.

Most people get it through an IV infusion, which can take a few hours and is usually done every 3 to 4 weeks. Some can receive it under the skin (subcutaneous), which allows for more frequent but smaller doses at home. Side effects are common but usually mild—headaches, chills, fatigue, or a low-grade fever. Rarely, more serious reactions like kidney problems or blood clots can happen, especially in older adults or those with existing health issues. That’s why doctors monitor you closely during and after treatment.

You might wonder why not just take pills or vaccines? Because these therapies don’t work the same way. Vaccines train your body to make its own antibodies over time. Immunoglobulin therapy gives you immediate protection, but it doesn’t last—so you need regular doses. It’s not a cure, but for many, it’s the difference between constant infections and living a normal life.

The posts below cover real-world issues people face with treatments like this: how to spot signs of infection when your immune system is weak, how to handle side effects at home, what to ask your doctor before starting, and how to avoid dangerous drug interactions. You’ll also find practical advice on managing chronic conditions that often require long-term antibody therapy—like how to track symptoms, reduce hospital visits, and stay safe while traveling. Whether you’re new to this treatment or have been on it for years, these guides give you the facts you need to take control.