What should you know about a skin prick test?

A clinician places small drops of allergen extracts on the forearm or back and gently pricks the surface through each drop. A control helps show how your skin responds, and the sites are checked after a short wait for an itchy raised area. The panel may include pollens, house dust mites, pets or foods, depending on your history. A positive reaction shows sensitisation; it must be matched with a reproducible pattern of symptoms. A negative test makes some allergies less likely but does not answer every cause of nasal, eye, chest or skin symptoms.

Tell the allergy team about medicines, pregnancy, skin conditions and previous severe reactions. Some antihistamines and other medicines can affect the result, so only stop them when the testing team gives clear instructions. Wear clothing that allows access to the test area and avoid scratching during the waiting period. Do not deliberately eat a suspected food or expose yourself to a trigger to test the result at home. The clinician may use the findings to guide avoidance, treatment or further testing.

Tell staff immediately if you develop widespread hives, throat tightness, wheezing, dizziness, vomiting or swelling during testing. After leaving, call emergency services for breathing difficulty, faintness, tongue or throat swelling, or rapidly worsening symptoms. A small itchy local bump usually settles as the test reaction fades; contact the testing service if a reaction remains severe or continues to expand.

Which allergens are relevant to my symptom pattern? Which medicines should I pause, and for how long? How will a positive result change my daily plan? Would blood testing or another assessment be more suitable for my skin or medical history?