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One itchy spot on your child’s skin isn?t likely to make you speed-dial the doctor. However, if your child wakes up with red marks covering his body, or you notice blotches on his face after lunch, you?re right to worry?and want answers.
What are hives"

Hives, or urticaria, are red raised welts on the skin. Individual hives may look like mosquito bites, but in large numbers, can resemble a rash. Fotini Kavadas, paediatric clinical immunologist and allergist at Alberta Children?s Hospital in Calgary, explains that hives occur when allergy cells in our body are attacked and release allergic chemicals called histamines. Hives can last for minutes, several hours or, in the case of chronic urticaria, can come and go for six weeks or more. They are typically itchy, but can also burn or sting. Top triggers

Hives have myriad causes, including allergies to food, medicine, animals, dyes or perfumes; physical forces, such as the skin being pressed or scratched; and viral infections (even the common cold). Heat, cold and emotional distress can also trigger hives, as Cari Mistry of Orangeville, Ont., knows all too well. ?I have a five-year-old son who, since the age of two, has gotten hives from being upset,? she says. ?If he?s crying wildly, he?ll break out on his face and torso.?
Sometimes there is a clear cause, but in other cases, figuring out why a child is getting hives can be extremely frustrating for parents. It took several years of hospital vis...