By Abbie Cornett
No one can argue that immune globulin (IG) therapy is a game-changer for people who require this lifesaving treatment. Unfortunately, it comes at a price, often in the form of side effects. Fortunately, when side effects occur, reactions are typically mild to moderate. And, while serious side effects can occur, they are rare. The good news is in almost all cases, effects can be controlled or even eliminated.
Side effects are quite different between intravenous IG (IVIG) and subcutaneous IG (SCIG) products. Even though both enter the bloodstream, IVIG is given into a vein (intravenously) via infusion that usually takes one to four hours. Because IVIG goes directly into a vein, there is a rapid spike in serum IgG. On the other hand, SCIG infusions, which have become increasingly popular in recent years, are given by slowly injecting purified IG into the fatty tissue just underneath the skin using a mechanical infusion pump.
The most common side effects of IVIG are flu-like symptoms, including headaches, fatigue, body aches and fever. Premedicating with acetaminophen is routine for most people, and if a headache occurs, the dose can be repeated. If headaches are severe, predosing with a steroid or migraine medicine may be appropriate. More serious side effects such as nausea, vomiting, neck pain or stiffness can signal a more serious adverse reaction known as aseptic meningitis. If patients experience these symptoms, a physician should be notified, and emergency medical attention may be needed.
Fluctuations in blood pressure can also occur during an IVIG infusion. The nurse administering IVIG should take a baseline blood pressure before starting the infusion, and the rate of infusion should be started slowly and gradually increased until the maximum rate is reached. Blood pressure should also be taken at intervals throughout the infusion. These precautions are essential if patients have a history of hypertension. If at any point patients do not feel well, blood pressure and other vital signs such as pulse, breathing rate and temperature should be reassessed. If blood pressure is high, the infusion should be paused and restarted when symptoms or blood pressure normalize. It is important to remember many reactions can be controlled by slowing the rate of infusion or pausing it until symptoms subside. Patients can also develop a rash, which does not necessarily mean they are allergic. In many instances, the rash can be treated with a premedication of steroids.
With SCIG, the drug is absorbed more slowly, and therefore, the potential for systemic reactions is greatly reduced. This makes SCIG a good option for patients who have experienced serious side effects with IVIG. Common injection site reactions to SCIG include redness, swelling and itching, which are usually mild and go away after a day or two. In many cases, these reactions are generally worse with the first few infusions and diminish over time.
Adverse reactions to SCIG are rare and usually mild, but they can include headaches, feeling hot, nausea, diarrhea, sore throat, rash, increased cough and back pain. Extremely rare are serious side effects such as allergic reactions, kidney problems or blood clots.1
One of the most important things patients can do to reduce side effects of treatment is to hydrate; drinking an adequate amount of water several days before the infusion, on infusion day and a few days after the infusion is critical. The only time patients should not increase their fluid intake is if they have a clinical reason not to.
1. Cook, AE. Benefits of Home IVIG Therapy. IG Living, April-May 2016. Accessed at
Accessed at https://www.igliving.com/magazine/articles/IGL_2016-04_AR_Benefits-of-Home-IVIG-Therapy.pdf.