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Sub-Q and IV immunoglobulin therapies

If you or a loved one receives a diagnosis of primary immunodeficiency (PI) disease, you’ll want to discuss the different treatment options with your physician. The options available depend on the type of PI disease. For the most common type of PI, antibody deficiencies, immunoglobulin (Ig) therapy is the typical treatment. The two common Ig therapy options are subcutaneous (Sub-Q) Ig and intravenous (IV) Ig, differentiated by the method of delivery.

A medical professional delivers an IVIg infusion through a vein in a healthcare setting. Sub-Q Ig is infused just below the skin using a small needle and an infusion pump and is typically self-administered by the patient or administered by a caregiver. Studies have shown both forms of Ig to be effective in preventing infection.

It’s important to have information about both therapy options when you’re talking with your doctor about which therapy is right for you.

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Which immunoglobulin therapy is preferable?

The answer depends on which you and your treatment team feel would work better for you.

Some people favor IVIg therapy because they prefer that a healthcare professional be in charge of administering their treatment and don’t mind taking time out of their day to go to an outpatient facility. Other people find weekly infusions too frequent, and want the 3- to 4-week schedule associated with IVIg.

Other patients prefer Sub-Q Ig because it allows for the freedom and flexibility of home administration. After adequate training by a healthcare professional, the patient can self-administer their weekly Ig treatment. This can be done at home or anywhere else one can reasonably infuse. Unlike IVIg, Sub-Q Ig doesn’t involve going to an infusion clinic or doctor’s office every month for treatment at a scheduled time, so the patient can avoid both travel time and time spent in the waiting room. In addition, Sub-Q Ig infusions are generally shorter than IVIg infusions.

When deciding between Sub-Q Ig and IVIg, you should be aware of the side effects associated with each. IVIg products have an FDA-required boxed warning for renal dysfunction, and the most common side effects include headache, pain, nausea, fatigue, and chills. Sub-Q treatment is often accompanied by mild-to-moderate injection-site reactions. Other common side effects for Sub-Q Ig include headache, vomiting, pain, and fatigue. Hypersensitivity and anaphylactic reactions can also occur, as can renal dysfunction. In addition, thrombotic events, aseptic meningitis syndrome, hemolysis, and transfusion-related acute lung injury could occur with either form of Ig therapy.

The important features of Sub-Q Ig and IVIg therapy are displayed in the table below. If after reading this material, you’re still unsure of which treatment is right for you, you may want to take our quiz to help you and your physician decide.

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Features of Sub-Q Ig and IVIg therapy

AdministrationWith adequate training, self-administered by patient or administered by a caregiver Administered by a medical professional, usually at a doctor’s office or clinic
Injection site Infused into the fatty tissue just below the skin’s first layer. Common infusion sites include the thighs, upper arms, stomach, and hips Delivered through a vein; commonly given in the arm
Frequency Weekly Every 3 to 4 weeks
Venous access Access to veins not required Requires accessible veins
Needle size (The higher the gauge, the smaller the diameter of the needle) 27-28 gauge needle 16-22 gauge needle
Level of immunoglobulins Steady Ig levels Highest Ig level immediately after infusion; lowest Ig level before the next scheduled infusion
Most common side effects Most common side effects are mild-to-moderate injection-site reactions; others include headache, vomiting, pain, and fatigue Most common side effects are those occurring throughout the body, called “systemic” side effects; headache, pain, nausea, fatigue, and chills are common

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Immunoglobulin quiz

Which type of immunoglobulin therapy—Sub-Q or IV—
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