Can you tell the difference between a cold and an allergy? It's not easy, because the symptoms are similar on the surface. These symptoms will help you distinguish a cold from an allergy:
Upper respiratory tract: A runny nose with cloudy nasal discharge and fever is probably a cold. The symptoms should go away in a week or so. But persistent, thin, watery nasal discharge may indicate allergies.
A rare and severe allergic reaction called anaphylaxis results in rapid swelling of baby's airways. This prevents baby from breathing or swallowing. If you think this is happening to your child, call 911.
Lower respiratory tract: Coughing and wheezing (noisy breathing in which your baby makes a whistling sound) are common in infants and toddlers. Babies have small, sensitive airways in their lungs. When the airways swell up as a result of a respiratory virus, babies tend to cough or wheeze. Sometimes coughing and wheezing are the result of asthma, a lower respiratory disease that affects about 15 percent of children in the United States.
Allergic babies are prone to respiratory viruses and have trouble getting rid of coughs or colds. In response to allergens and viruses, the muscles of baby's airways haves spasms and swell, leading to a dry, hacking cough. This can progress to wheezing.
Wheezing can be dangerous in a small child because it's an indication that the child is having trouble breathing. If you think your child may be wheezing, observe whether his breathing is noisier when he breathes out or in, whether he's sucking in his chest or stomach or flaring his nostrils to breathe, and whether he seems uncomfortable. If you think your child is showing any of these symptoms, call your doctor right away.
Eyes: Conjunctivitis, or pinkeye, is a condition caused by both allergies and viruses. Its symptoms are a red eye and discharge that causes the eye to be crusted shut in the morning. Allergic conjunctivitis doesn't look very different from pinkeye that's caused by a virus, so your child's pediatrician will need to make the diagnosis.
There are, however, some things you may notice that are more specific to allergy-induced pinkeye. Babies with allergies may rub their eyes frequently (allergic eyes tend to be itchy), tear excessively, have dark circles under the eyes, and be irritable.
Skin: Newborns are prone to rashes, but most rashes (including infant acne) vanish by 2 or 3 months of age. This is the time allergic rashes tend to appear. The most common allergic rash is atopic dermatitis, or eczema, and for many babies it's the first warning sign of allergic tendencies. Eczema is a red, scaly, and sometimes oozing rash on baby's cheeks, torso, arms, and legs. In toddlers and older children, it appears as persistent dry, itchy patches of skin, usually on the neck, wrists, and ankles, and in the creases of the elbows and knees.
Contact dermatitis is an allergic rash caused by a reaction to soap, detergent, wool clothing, poison ivy, or another irritant that has touched baby's body.
The classic allergic rash -- the itchy, welt-like hive -- is relatively rare in infants, and when it does occur tends to be smaller than in older children and adults (usually less than an inch long).
Stomach: Viruses can cause vomiting, diarrhea, upset stomach, and gassiness. But these symptoms can also result from allergies -- and not just to food. Children with environmental allergies may have stomach ailments as a result of swallowed phlegm, which can irritate the stomach.
Behavior: Problems with eating, sleeping, or irritability can result from allergies. Your allergic baby will be fussy and uncomfortable. That's usually due to his chronic congestion, abdominal pain, or itchy skin, eyes, or nose.
Another clue to look for is when symptoms occur. Colds are more common in the winter, but indoor allergies (such as a dust mite allergy) may be present all year. A food allergy can manifest itself anytime from a few minutes to a few hours after the offending food is eaten. Seasonal hay fever is most common in the spring or fall, but it usually doesn't affect babies.