IgE

You should get an IgE test if you have frequent sneezing, runny or blocked nose, itchy eyes, wheezing, skin rashes, hives, or eczema, or suspected food or drug allergies. It is also recommended for asthma, suspected parasitic infections, or ABPA, and for children with recurrent allergic symptoms.

No special preparation or fasting is required for an IgE test. Unlike skin allergy tests, antihistamines do not affect blood IgE results, so you can usually continue them. Inform your doctor about steroids, immunosuppressants, or allergy treatments like omalizumab, and mention any recent allergic reactions or infections.

No, fasting is not required for an IgE test. You can eat and drink normally before giving your sample. You can usually continue antihistamines, as they don't affect blood IgE results. Inform your doctor about any steroids or allergy treatments you take, and follow your lab's instructions.