Why does a 4-month-old baby sweat excessively during sleep?

Generally, excessive sweating during sleep in a 4-month-old baby may be caused by factors such as high ambient temperature, vigorous metabolism, vitamin D deficiency, spleen and stomach weakness, or tuberculosis infection. The details are as follows:

1. High external temperature

If the baby is wrapped in too many blankets, it may lead to poor heat dissipation and result in excessive sweating. In such cases, proper cooling measures and increased fluid intake can quickly alleviate the sweating.

2. Vigorous metabolism

Babies at four months of age have a particularly active metabolism, which can naturally lead to increased sweating. Caregivers should adjust the baby's clothing according to seasonal changes and weather conditions, avoiding overdressing the baby, which can exacerbate sweating. This is a normal physiological phenomenon and usually does not require special treatment.

3. Vitamin D deficiency

Excessive sweating may be related to vitamin D deficiency. Babies may also show symptoms such as irritability, increased nervous excitability, severe crying at night, and枕秃 (loss of hair at the back of the head). Parents can let the baby get more sun exposure and, under medical guidance, administer supplements such as cod liver oil or vitamin AD softgel capsules to correct the deficiency.

4. Spleen and stomach weakness

Babies with weak spleen and stomach function tend to sweat during sleep, primarily due to overfeeding, which impairs the digestive system and leads to spleen and stomach deficiency and subsequent sweating. Under medical advice, medications such as Shenling Baizhu Granules or Pediatric Spleen-Strengthening Oral Liquid may be given to improve digestion and strengthen the spleen and stomach.

5. Tuberculosis infection

Tuberculosis infection should be considered if there is a family history of tuberculosis exposure. A positive tuberculin skin test and chest X-ray findings suggestive of tuberculosis lesions support the diagnosis. Clinical manifestations often include low-grade fever, excessive sweating, and weight loss. Standard anti-tuberculosis treatment is required. Parents should take the baby to the hospital for evaluation; if tuberculosis is confirmed, prompt anti-tuberculosis therapy should be initiated.

It is recommended that parents seek timely medical attention when the baby shows any concerning symptoms and follow standardized treatment under a doctor’s guidance to promote recovery.