Celery is an edible plant that can either be cooked or eaten raw. It is also useful as a mild spice because of its distinct flavour. The plant has numerous beneficial chemicals and compounds that help lower sugar levels and blood pressure and induces sleep. Similarly, certain compounds in the plant can also trigger adverse reactions in the body that could cause allergies. Since food allergies depend greatly on an individual’s genetic make-up, it is important to take an allergy test for celery and confirm the condition. Celery allergy can be mild or severe depending on an individual’s immune system. Usually, the allergic reaction begins within 2 hours of consuming celery, and it might show different symptoms for different individuals. Some of the symptoms one can notice before taking the celery allergy test are: Abdominal pain and stomach cramps Vomiting and diarrhoea Feeling of nausea Itching on the skin that eventually leads to eczema Tightness or swelling in the throat Pale or blue coloured skin  Slow pulse rate and dizziness  Cardiac collapse  Anaphylaxis  Itchiness in the lining of the mouth Scratchy throat Swelling in the lips, mouth, throat, itchy and tongue Celery allergy also leads to different skin reactions that might make the skin sensitive to sun exposure. As a result, the skin might show blisters as soon as you go in the sunlight. Furthermore, contact with the vegetable can also cause severe swelling in the skin alongside contact dermatitis. Since food allergies also depend on the amount of fruit or vegetable you consume, it is essential to go for a celery allergy test. The allergy test for celery is based on IgE testing for a specific condition. The possible allergens in the celery are Bet v 1, chlorophyll antibody-binding protein, profilin, and a lipid transfer protein. Some of the allergens in celery are heat stable and do not degrade even after cooking. These are usually vital allergen proteins in the plant. On the other hand, allergens like profilin are heat unstable and affect the body only when consumed in a raw form. The celery allergy test also confirms the presence of cross-reactivity with fruits like peach, kiwi, melons, and pistachio and vegetables like carrot, tomato, and broccoli. The celery allergy test uses an antibody detection technique using flow cytometry. This is a scientific technique that labels the surface proteins with fluorescent probes. Henceforth, the labelled samples pass through a cell sorter and are detected by optical and electronic mechanisms. An allergy test for celery is essential as celery induces phototoxicity. Hence, it is necessary to identify the condition before it produces severe symptoms in the body.  Medically reviewed by Dr. Jatin Ahuja, Infectious Diseases, Apollo Hospitals Indraprastha, South Delhi.