A: Jenna, your daughter’s persistent congested and runny nose and sneezing can be signs of a respiratory allergy, commonly called “allergic rhinitis.” Allergic rhinitis is the response of the nose and sinuses to airborne allergens, substances that cause an allergic reaction. These are commonly dust mites, pollen, mold and animal dander. Some children with allergic rhinitis also snore and have an itchy nose and throat, red/watery/itchy eyes, dark under-eye circles, mouth breathing, nighttime coughing and recurrent ear infections.

Occasionally, children get allergic rhinitis symptoms from food allergies, but that is usually associated with mouth itching, vomiting, diarrhea or skin rashes after eating certain foods. Since allergies can be hereditary, your daughter is more likely to have them if either parent has or both parents have allergies, asthma or eczema.

While food allergies can develop in the first year of life, most respiratory allergies do not develop until the second year or later, after children have been exposed to allergens over time. Allergy to indoor allergens such as dust mites and pets becomes more common throughout early childhood. Allergy to outdoor allergens such as pollens occurs most commonly after 3 and reaches a peak in the teen years. Year-round allergies are more common in young children and seasonal allergies are more common in children over 6.

Discuss your concerns about your daughter with your pediatrician. The doctor may prescribe an anti-allergy medication. There are many different types, such as antihistamines, steroids and decongestants. Some are available as oral medications and others as nasal sprays. Some are over-the-counter and some require a prescription.

The doctor may also suggest some general strategies to prevent allergies:

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• Make sure your home and car are smoke-free.
• Keep down the dust in your home, especially your daughter’s room. Get allergy-proof plastic covers for your daughter’s mattress and pillow. Wash bedding and stuffed animals in hot water every week. Wet mop floors and vacuum carpets frequently, when your daughter is not around. Keep your furnace filters clean.
• Fix water leaks and use the bathroom fan to avoid household mold.

If the allergy-prevention steps and medications do not help, your doctor may refer you to an allergist, a doctor specialized in the field of allergy. The allergist will ask you more questions and do allergy tests, which can confirm whether your daughter has allergies, and identify what she is allergic to.

There are two basic types:

• Blood tests: A pediatrician or allergist could order these. A small amount of your child’s blood is taken for the “RAST” (radioallergosorbent test), which detects the child’s immune system response with IgE antibodies to specific allergens. The RAST has the advantage of not being affected by a skin rash or use of antihistamine medications.
• Skin tests: An allergist generally performs these. Small amounts of different allergens are gently injected or pricked into your child’s skin, usually the back or forearm. Redness and swelling at the site indicates an allergy. The skin tests tend to be more sensitive or accurate than blood tests.

Based on the allergy test results, the allergist will suggest more specific prevention steps and may prescribe different medications. If these don’t help, a series of allergy shots over time may be recommended.