Fresh green celery in the market
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Along with allergies to peanuts, celery allergies affect Americans more frequently than adverse reactions to other foods. Some people only have problems with celery at certain times of the year. This type of allergic reaction is due to cross-reactivity to birch trees or wormwood plants, which share a particular cell structure with celery. Oral syndromes occur most often during birch or wormwood pollination seasons. Other patients may experience allergy symptoms from eating cooked or uncooked celery anytime. Consequences range from simple itching to life-threatening metabolic collapse.

Mouth Itching

Oral symptoms may represent the extent or just the beginning of the physical effects of celery allergies. A tingling or itching sensation begins in the mouth during this type of allergic reaction. Moderate itching in the lips, tongue and throat occurs a minute or two after the body absorbs celery allergens.

Facial Swelling

Because itches can arise at any time, patients may discount those allergy symptoms unless inflammation and swelling accompany them. Many patients with oral celery allergies get raised bumps in the mouth and nothing more. Others experience further swelling in the lips, tongue and throat. The University of Maryland Medical Center reports that additional areas of the skin, such as the face and eyelids, may show visible swelling.

Difficulty Breathing

While oral allergy symptoms usually remain benign, more severe allergic reactions can occur at any time. As the National Institutes of Health relates, swelling in the mouth and throat can block the airways or cause them to become constricted. Symptoms of wheezing, coughing and breathing trouble indicate the onset of anaphylaxis, a condition brought on by celery allergies that can quickly escalate to life-threatening proportions. The NIH advises calling 911 immediately for paramedic assistance.

Uneven Pulse

Anaphylactic shock sets in shortly after eating celery, as breathing obstructions reduce the flow of oxygen throughout the body. Patients may experience a racing, uneven or weak pulse. The NIH notes that confusion, slurred speech and light-headedness may be noticeable signs of a system-wide shock that can lead to loss of consciousness, cardiac arrest and death.

Digestive Problems

Less dramatic allergic reactions to celery go on to affect the digestive tract and then fade away as allergens exit the body. UMMC notes that these allergy symptoms may not begin until an hour or more after eating, when patients may suddenly be overcome by nausea. Although abdominal pain, stomach cramps, vomiting and diarrhea can be severe, the entire episode should fade completely in a short time. Patients who continue to eat celery, however, will risk subsequent reactions.