Allergic reactions are one of those classic pediatric conditions that typically scare parents, even when they are causing mild symptoms.
Perhaps it is because most allergy symptoms, especially when caused by a food allergy, insect sting, or allergy to a medication, typically come on suddenly and can cause symptoms that parents aren't used to seeing.
Classic allergy symptoms and signs, some mild and some more severe, can include:
- angioedema (a swollen tongue or swelling around a child's eyes and lips, etc.)
- difficulty breathing
- itching in a child's mouth or throat
- abdominal pain
- low blood pressure (hypotension)
- loss of consciousness
Most parents would be concerned if their child had an allergic reaction triggering any of these symptoms. However, mild congestion and coughing -- or even hives that quickly come and go -- would likely not be as big a worry as some of the other more severe symptoms of an all-out anaphylactic reaction.
An anaphylactic reaction, with coughing, wheezing and difficulty breathing, itching in the throat, vomiting, and dizziness, is a life-threatening allergic reaction that requires immediate medical attention.
On the other hand, a child who just has hives and no other symptoms might just need an age-appropriate dose of an antihistamine, such as Benadryl (diphenhydramine).
What about a swollen tongue?
A swollen tongue sounds like a serious symptom that should be a medical emergency, doesn't it? While a swollen tongue can be a serious symptom, it is important to consider what other symptoms your child has at the same time, and to consider some of the things that can cause a child's tongue to become swollen.
As part of an allergic reaction, a child may get hives on his tongue or lips, in addition to the more classic hives on his skin.
An allergic reaction can also trigger another type of swelling that cause a swollen tongue. This type, called angioedema, leads to swelling beneath the surface of the skin, but the result is basically the same -- a swollen tongue.
Like other allergic reactions, both hives on the tongue and angioedema can be triggered by food allergies, drug allergies, a bite or sting from an insect to which your child is allergic, or almost anything else that can trigger your child's allergies.
Without other more serious symptoms, such as difficulty breathing or swallowing, a swollen tongue is likely a part of a more mild allergic reaction, but parents should still call their pediatrician in case their child needs more aggressive treatment.
Non-Allergic Causes of a Swollen Tongue
In addition to allergies, non-allergic causes of a swollen tongue can include:
- an infection in or on the tongue
- a tumor or mass
- an insect bite or sting on the tongue that causes swelling, even though it might not trigger an allergic reaction
Keep in mind that these other causes either occur slowly over time, or it is a little more obvious why your child's tongue is swollen. For example, he may have had a viral infection that caused ulcers on his tongue and then triggered a secondary bacterial infection, or he may have told you he got stung on his tongue by a bee.
Kliegman: Nelson Textbook of Pediatrics, 18th ed.
Adkinson: Middleton's Allergy: Principles and Practice, 6th ed.