When someone has an allergy, her immune system treats a particular substance like an invader, attempting to fight it off by releasing chemicals. These chemicals irritate the body and cause allergy symptoms that can range from uncomfortable to dangerous, depending on the severity of the allergy. Identifying allergies in an infant is challenging, but symptom awareness can help parents take proactive and preventative measures.
Allergens
An allergen is a chemical or substance that can cause an allergic reaction, according to the National Institutes of Health and National Library of Medicine website Medline Plus. People that do not have allergies can be exposed to allergens and experience no physical response. Common allergens include insects, bacteria, viruses, chemicals, drugs, foods, dust, pollen and even plants. Food allergens in particular plague infants. According to KidsHealth, between one and 7.5 percent of infants are allergic to the proteins found in cow's milk and milk-based formulas. Soy allergies are also more prevalent in babies, and approximately one-third of those infants allergic to cow's milk are also allergic to soy.
Allergy Types
There are several different types of allergies. A skin allergy occurs after an infant or child touches something and has an allergic reaction on his skin. Nasal or respiratory allergies occur when an allergen gets inhaled or perhaps ingested. When the allergy develops after eating the reaction is often gastrointestinal in nature. Skin reactions can also occur with food and insect allergens.
Symptoms
Symptoms can develop over time or occur right away and can occur intermittently or in a continuous fashion. Infants are most likely to develop gastrointestinal or nasal allergies. Nasal allergy symptoms often mimic those of a cold but usually last longer. They can include a stuffy or clear runny nose, dry cough, frequent sneezing and itchy, red or watery eyes. Many babies with allergies will wiggle or wipe their noses by pushing it up in what BabyCenter refers to as an "allergic salute." Some may even appear to have dark circles under their eyes, which doctors often refer to as allergic shiners. Kids with nasal allergies are also more prone to ear infections, asthma and sinus infections.
Food allergy symptoms in infants can include hives, an eczema-like rash, a runny or itchy nose. Babies may also experience vomiting or diarrhea. Insect allergies can also produce hives and diarrhea. People with severe allergies are at risk for anaphylactic shock, considered a medical emergency because symptoms include difficulty breathing and throat swelling.
Causes
Genetics or heredity influence allergies in infants and children, although KidsHealth notes there are always exceptions. Allergic parents do not always give birth to children with allergies, and plenty of children develop allergies despite an allergy-free family history
A child with one parent with an allergy has a 50/50 chance of developing some sort of allergy, according to BabyCenter. When both parents have allergies, this probability increases to 80 percent. However, just because a child has a biological leaning toward developing an allergy does not necessarily mean she will develop the same allergies as her parents.
Diagnosis
Allergists perform skin tests for common food and environmental allergies, which involve injecting small amounts of allergens into the surface of the skin and analyzing the patient's reaction. Although doctors can perform these tests on infants, many consider the results more reliable when a child is older than two years of age and has had time to develop a reaction. A more expensive allergen blood test is available for when doctors anticipate a severe allergic reaction; however, the BabyCenter website says skin test results are more reliable with infants.
Doctors recommend reevaluating an infant in six to 12 months if a skin test comes back negative but allergy symptoms persist.
