Itchy mouth after eating fruit? It could be pollen causing trouble

Why does eating fruit make your mouth itch?

Some people get an itchy or tingling feeling on their lips, tongue or throat after eating apples, peaches or carrots, and sometimes mild swelling. This reaction often starts within minutes. It is usually not serious, but it is very uncomfortable. It has a name: oral allergy syndrome.

Oral allergy syndrome happens when the immune system mistakes proteins in some fruits and vegetables for pollen. If you are allergic to birch pollen, a protein in apples has a structure similar to birch pollen. Your immune system "mistakes" it and starts a small allergic reaction in your mouth.

Which pollens and foods often cross-react?

Some pairings of pollen and food are more common. People allergic to birch pollen may get an itchy mouth from apples, pears, cherries, peaches, plums, apricots, kiwi, carrots, celery and hazelnuts. People allergic to mugwort pollen may react to celery, carrots, fennel, coriander and sunflower seeds.

People allergic to grass pollen may sometimes feel uncomfortable after eating tomatoes, potatoes or melon. People allergic to ragweed pollen may get an itchy mouth from bananas, cucumbers, courgettes or melon. These pairings are not fixed. Everyone is different, so you need to pay attention to your own reactions.

Do symptoms get better after heating?

Many proteins that cause an itchy mouth are sensitive to heat. Heating changes their structure, so the immune system is less likely to recognise them. So some people get an itchy mouth from raw apples but are fine with apple pie, apple sauce or cooked apples. Carrots and celery may also become "safe" after cooking.

But not all foods work this way. For example, some people still react to celery even after it is heated. Also, reactions to foods such as peanuts and nuts are often different from oral allergy syndrome, and heating usually does not solve the problem. If you are not sure, it is best to try a small amount first and watch for a reaction.

See a doctor right away if these happen

Oral allergy syndrome usually stays in the mouth and throat, and symptoms are mild. But if the following signs appear, the reaction may be getting worse and you need to see a doctor right away:

· Tight throat, hoarse voice, trouble swallowing, or a feeling that your throat is swollen; · Shortness of breath, wheezing, or constant coughing; · Urticaria (hives) all over the body, or clear swelling of the face or lips; · Dizziness, a racing heart, pale skin, or cold sweats; · Nausea, vomiting, or stomach pain.

These may be signs of anaphylaxis. Do not wait. Call 120 (the emergency number in China) or go to the emergency department right away. If a doctor has given you emergency medicine before, use it as instructed.

How to cope day to day and keep a record

If it is only an itchy mouth and there are no other symptoms, you can try cooking the fruit before eating it, or peeling it first. For some people, the reaction is linked to the pollen season. It may be more obvious during the pollen season and may not happen outside it. You can write down the food you ate, your symptoms and when they started. This helps your doctor work out what is going on.

Do not cut out lots of foods out of fear. If symptoms keep coming back or bother you, it is a good idea to see an allergy specialist. A skin prick test or a blood test can help identify the allergen. Your doctor will give you dietary advice and a plan based on your situation.

This article is for general information only and is not medical advice. Please follow your doctor's instructions.