IgG
IgG (immunoglobulin G) is the most abundant antibody in the blood and provides long-term protection against infections. It is the only antibody that can cross the placenta to protect a developing fet…
Category: Inflammation & Immune
Also known as: igg, immunoglobulin g, serum igg, Immune globulin G
Reference range: 700–1600 mg/dL (Source: ABIM)
Standard unit: mg/dL
High values may indicate
High IgG levels may indicate chronic infections, autoimmune disorders (such as lupus or rheumatoid arthritis), liver disease, IgG myeloma, or sarcoidosis.
Low values may indicate
Low IgG levels may indicate common variable immunodeficiency, primary immunodeficiency disorders, nephrotic syndrome, or conditions causing protein loss, and increase susceptibility to infections.
Frequently asked questions
- What is a normal IgG level?
- A typical reference range for IgG is 700–1600 mg/dL (source: ABIM). Reference ranges vary by laboratory, age, and sex, so always compare against the range on your own lab report.
- What units is IgG measured in?
- IgG is most commonly reported in mg/dL. Labs in different countries may use other units — you can convert between them with BloodId's blood test unit converter.
- Where do IgG reference ranges come from?
- BloodId uses ABIM standard reference ranges and educational information from MedlinePlus (see our methodology). Reference ranges still vary by lab, age, and sex, so always compare against your own report.
- Can I track IgG over time?
- Yes. Upload results from any lab and BloodId charts your IgG over time against its reference range, so you can see whether the trend is rising, falling, or stable.