Melon allergy

About melon allergy

Melon, including cantaloupe, honeydew and watermelon, is a common trigger of pollen-food syndrome (oral allergy syndrome), especially in people allergic to ragweed or grass pollen. This happens because the immune system makes IgE antibodies against pollen proteins that closely resemble proteins in raw melon, so the body reacts to the fruit as though it were the pollen. Melon contains a widely shared protein called profilin, which explains why reactions often go together with other fruits and vegetables.

Because it is usually pollen-driven, reactions tend to be mild and start quickly, generally within minutes of the raw fruit contacting the mouth. Typical symptoms are an itchy or tingling mouth, lips, tongue and throat, sometimes with mild swelling. The proteins involved are fragile, so cooked melon is often tolerated, though melon is rarely cooked. Occasionally reactions are more generalised. There is well-recognised overlap with other profilin-containing foods such as watermelon, banana, cucumber, courgette and tomato, and symptoms often flare during the relevant pollen season.

Diagnosis is guided by your history and can be supported by skin-prick testing, often with fresh fruit, or specific-IgE blood tests. Management centres on avoiding raw melon if it triggers you and being aware of the linked fruits and vegetables. Most people manage well with simple avoidance, but if you ever develop widespread swelling, wheeze or faintness, treat it as a possible severe reaction: in the UK call 999 and use an adrenaline auto-injector if one has been prescribed.