What symptoms can occur after a food allergy?

After a food allergy, patients may experience a variety of symptoms, mainly including: 1. Gastrointestinal symptoms: such as vomiting, diarrhea, abdominal pain, bloating, gastroesophageal reflux, etc. Severe cases may even develop bloody stools, gastrointestinal bleeding, enteropathy, or severe colitis. 2. Skin symptoms: skin manifestations such as hives, eczema, itching, and swelling (e.g., swelling of the face, lips, or eyelids). Severe cases may develop allergic purpura or acute laryngeal edema leading to airway obstruction. 3. Respiratory symptoms:表现为 runny nose, sneezing, coughing, wheezing, difficulty breathing, etc. In severe cases, asthma attacks or acute laryngeal edema may occur. 4. Eye symptoms: such as itchy eyes, tearing, blinking, and conjunctival congestion. 5. Systemic allergic reactions: including swelling of the throat and tongue, sudden wheezing or difficulty breathing, shock symptoms (e.g., dizziness, pallor, decreased blood pressure, loss of consciousness), as well as cold, clammy skin and excessive sweating.