What should I do if my baby gets heat rash?

In general, infant heat rash may be caused by factors such as excessively high temperature and humidity in the environment, non-breathable and non-absorbent clothing, mild infection associated with heat rash, secondary eczema following heat rash, or skin damage and infection accompanying heat rash. It is recommended to seek medical attention promptly, identify the underlying cause, and then improve the condition under a doctor's guidance through general management, medication, and other treatments. Specific analyses are as follows:

1. Excessively high environmental temperature and humidity: High ambient temperature and humidity can block sweat gland ducts in infants, preventing normal excretion of sweat. The accumulated sweat beneath the skin leads to heat rash, presenting as small red papules. Maintain good indoor ventilation, keep room temperature between 22–25°C and humidity at 50%–60%, and avoid stuffy, hot conditions.

2. Non-breathable and non-absorbent clothing: Dressing infants in synthetic fiber or tight-fitting clothes that cannot absorb sweat causes perspiration to remain on the skin surface for prolonged periods, making heat rash more likely. Choose loose, breathable cotton clothing with appropriate thickness, change clothes frequently, and keep the infant’s skin dry and clean.

3. Heat rash with mild infection: After heat rash lesions break open, they become susceptible to bacterial invasion, leading to mild infection characterized by small white pustules at the top of the rash. Patients should follow medical advice to use medications such as calamine lotion, mupirocin ointment, or erythromycin ointment to relieve itching and treat infection.

4. Heat rash complicated by secondary eczema: Prolonged unresolved heat rash can irritate the skin and trigger eczema, manifesting as increased redness and itching in the affected area, accompanied by flaking or scaling. Under medical guidance, patients may use medications such as desonide cream, hydrocortisone butyrate cream, or zinc oxide ointment to reduce inflammation and itching.

5. Heat rash with skin breakdown and infection: Infants scratching at heat rash can cause skin damage, allowing bacteria to multiply and lead to more severe infections, resulting in pustules, redness, and swelling. In such cases, patients should use medications as directed by a physician, such as fusidic acid cream, compound polymyxin B ointment, or cefaclor oral suspension, to control the infection.

In daily care, avoid bathing the infant too frequently—2–3 times per week is sufficient. Keep bath water temperature between 32–38°C. After bathing, gently pat the skin dry with a soft towel instead of rubbing. Avoid applying heavy or greasy skincare products to minimize burden on the infant’s delicate skin.