What should I do if a one-week-old baby has diarrhea?

Diarrhea, commonly referred to as "loose bowels," is a frequent condition in newborns during their first week of life. Common causes include lactose intolerance, indigestion, irritable bowel syndrome, intestinal dysbiosis, and acute gastroenteritis. Treatment typically depends on identifying and addressing the underlying cause. Detailed analysis is as follows:

1. Lactose Intolerance

Some babies are born with insufficient levels of lactase, the enzyme needed to break down lactose. After breastfeeding or formula feeding, these infants may develop lactose intolerance, leading to persistent diarrhea and bloating. In such cases, feeding should be switched to lactose-free dairy products under medical guidance.

2. Indigestion

In the first week after birth, a baby's digestive system is still immature and relatively weak. Overfeeding or preparing formula too concentrated can overload the digestive system, resulting in indigestion accompanied by symptoms such as diarrhea, bloating, and abdominal pain. These discomforts can be alleviated through proper feeding practices, along with gentle warm compresses and clockwise abdominal massage to reduce gastrointestinal stress and promote intestinal motility.

3. Irritable Bowel Syndrome (IBS)

A newborn’s digestive organs are not yet fully developed. When frightened or improperly fed, the infant may experience gastrointestinal motility disorders, leading to irritable bowel syndrome, which manifests as diarrhea, bloating, and vomiting. For significant diarrhea, medications such as smectite powder or live bacterial preparations like *Bacillus subtilis* bifidus granules may be used under medical supervision to regulate intestinal function and reduce bowel movement frequency.

4. Intestinal Dysbiosis

Cool or cold diets, impaired intestinal immunity, and other factors may disrupt the balance of gut flora in newborns, causing intestinal dysbiosis. This condition often presents with noticeable diarrhea, and may also include reduced appetite or refusal to feed. As directed by a physician, treatment with probiotics such as *Bacillus licheniformis* capsules or *Clostridium butyricum* capsules can help restore microbial balance and relieve symptoms.

5. Acute Gastroenteritis

Newborns in their first week are particularly vulnerable. If they consume spoiled breast milk or formula contaminated with pathogens such as *Salmonella* or *Vibrio parahaemolyticus*, they may develop acute gastroenteritis. Symptoms include vomiting, diarrhea, and fever. Under medical supervision, antibiotics such as cefaclor granules or cefuroxime axetil granules may be prescribed to control intestinal infection and inflammation.

Newborns have low resistance and underdeveloped immune systems. Any signs of illness should be promptly evaluated and treated at a hospital to prevent worsening of the condition.