Urticaria, commonly known as hives, is a frequent skin reaction affecting infants and children. The rash develops when skin cells release histamine, causing small blood vessels to leak fluid. This fluid accumulation beneath the skin creates the characteristic bumps. Understanding the appearance of these welts, common causes, and when to seek medical attention helps parents manage this condition.
Identifying the Look and Feel of Hives
Hives typically manifest as raised, swollen welts or plaques that appear suddenly anywhere on the baby’s skin. These individual lesions, often called wheals, resemble mosquito bites but vary significantly in size, from a pinhead to large patches. In lighter skin tones, the color is usually pink or red, sometimes with a pale center where swelling is concentrated. On darker skin tones, the rash may appear as slightly lighter or darker spots, making the raised texture the most noticeable feature.
Hives are transient; they frequently change shape, move across the body, and disappear entirely within a few hours, only to reappear elsewhere. Pressing on the center of a hive causes it to momentarily turn white (blanching), which helps identify the rash.
Hives are quite itchy, causing discomfort and fussiness in an infant. The rash may also be accompanied by a burning or stinging sensation.
Common Triggers Specific to Infants
In infants, hives are most frequently linked to an underlying infection rather than an allergic reaction. Viral infections, such as the common cold or other upper respiratory illnesses, cause over 40% of acute cases in children. The immune response to fighting the virus results in the skin reaction, meaning the hives are often a temporary symptom of the body resolving the infection.
While less common, food and medication can also trigger acute hives. Common food allergens like cow’s milk, eggs, peanuts, and tree nuts may cause a reaction, usually within two hours of ingestion. Certain antibiotics are another recognized source.
Environmental factors like temperature extremes, friction, or contact with irritants such as soaps or detergents can also cause localized reactions.
Soothing Hives and Monitoring Changes
Once the rash is identified as hives and is not accompanied by severe symptoms, the focus shifts to comforting the infant and minimizing itchiness. Applying a cool compress or a washcloth soaked in cool water provides temporary relief from stinging and itching. Lukewarm baths, particularly those prepared with colloidal oatmeal, also help soothe the skin.
Parents should dress the baby in loose-fitting, soft cotton clothing to prevent friction and overheating, as heat can make hives worse. Keep the baby’s fingernails trimmed or use baby mittens to prevent scratching, which can irritate the welts and potentially lead to secondary skin infections. Tracking the duration and frequency of the rash is helpful, noting whether the hives resolve within a day or two or if they persist.
Antihistamine medications, which block the effects of histamine, are sometimes used to treat hives. Parents should never administer over-the-counter antihistamines to an infant without explicit direction from a pediatrician. A doctor can determine the appropriate non-sedating medication, like cetirizine or loratadine, and provide the correct dosage based on the baby’s age and weight. Consulting a healthcare provider ensures the medication is safe and necessary.
Warning Signs Requiring Urgent Care
While most cases of hives in infants are mild and resolve on their own, the rash can occasionally signal a severe, life-threatening allergic reaction called anaphylaxis.
Immediate emergency medical attention is required if the hives are accompanied by any sign of difficulty breathing, such as persistent coughing, wheezing, or noisy breathing. Swelling of the face that extends to the lips, tongue, or throat (angioedema) is another serious symptom.
Other indicators of a severe systemic reaction include sudden, severe vomiting or diarrhea. If the infant exhibits signs of circulatory distress, such as extreme lethargy, paleness, or fainting, call emergency services immediately. These symptoms indicate that the allergic reaction is affecting more than just the skin and requires prompt intervention.