What happens at an allergy test?
Last updated September 3, 2026.
Two main kinds: a skin test, where drops of allergen on lightly pricked skin are read in about 15 minutes, and a blood test measuring IgE antibodies to specific allergens. A positive skin reaction looks like a small mosquito bite and fades within an hour or two. Blood testing fits when skin conditions, unstoppable medications, or severe-reaction risk rule out the skin version.
What to do
- Stop antihistamines as instructed. They blunt skin-test reactions - the pause is usually several days.
- List your suspects. Seasonal, food, pet, dust patterns from your own history sharpen the panel chosen.
- Expect mild itching, briefly. Positive bumps itch like bites and fade within the hour.
- Use the results. A named list enables real avoidance, the right medication, and sometimes immunotherapy.
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