Diarrhea in children is defined by three or more watery bowel movements per day, signaling that the intestine is not absorbing enough water or is secreting excess fluid. While most episodes are brief and resolve quickly, the rapid loss of fluids and salts can quickly lead to dehydration, which is the main danger, especially for infants and toddlers. Understanding the typical timeline and recognizing signs of fluid loss ensures timely intervention.
Typical Duration and Common Causes
The majority of diarrhea episodes in children are classified as acute, meaning they are brief and self-limiting. Acute diarrhea generally lasts less than one week, with many cases resolving within one or two days. The upper limit for acute diarrhea is considered to be 14 days.
The most frequent cause of acute diarrhea is viral gastroenteritis, often referred to as “stomach flu” or “gastro.” Viruses like Rotavirus and Norovirus are highly contagious and cause the intestine to swell and secrete fluid. Viral infections may begin with vomiting and a low-grade fever, with the diarrhea phase lasting up to a week or ten days.
Other causes include bacterial or parasitic infections, which are less common but can cause more severe symptoms. Diarrhea can also be triggered by non-infectious factors, such as a reaction to a course of antibiotics or a sensitivity to certain foods. Antibiotics disrupt the balance of healthy bacteria in the gut, leading to diarrhea that usually subsides shortly after the medication is stopped.
Diarrhea lasting longer than two weeks is classified as persistent or chronic and warrants a medical evaluation. Chronic diarrhea may be linked to underlying issues like food intolerances, such as temporary lactose intolerance following an infection, or conditions like celiac disease. In toddlers, chronic non-specific diarrhea can sometimes be traced to excessive consumption of fruit juice or other highly sweetened liquids.
Monitoring for Dehydration
The greatest risk associated with diarrhea is dehydration, which occurs when the body loses more fluid and electrolytes than it takes in. Children, particularly infants, can become dehydrated quickly, making careful monitoring necessary.
Signs of Mild to Moderate Dehydration
Mild dehydration is indicated by increased thirst and a dry mouth or tongue. In infants, this may also manifest as being less interactive or playful. Moderate dehydration involves decreased urination, meaning fewer than three wet diapers in 24 hours for older children and fewer than six for infants. Signs of more significant fluid loss include a lack of tears when crying and sunken eyes. For babies, the fontanelle (the soft spot on top of the head) may appear sunken.
Signs of Severe Dehydration
Severe dehydration is suggested by lethargy, extreme sleepiness, or a rapid heart rate, which require immediate medical attention. In older children, a severe sign is skin that remains tented for two seconds or more after being gently pinched, indicating significant loss of elasticity.
Home Care and When to Call the Doctor
The primary goal of home care is to prevent or reverse dehydration by replacing lost fluids and electrolytes. Oral Rehydration Solutions (ORS), such as Pedialyte, are the most effective way to restore the correct balance of water and salts. These solutions should be offered in small, frequent amounts, especially after each large, watery stool.
Parents should avoid giving children highly sugary drinks like fruit juices, sodas, or sports drinks, as their high sugar content can pull water into the intestine and worsen the diarrhea. For infants, breastfeeding or formula feeding should continue, often with smaller, more frequent feedings. Once vomiting has stopped, reintroducing a normal diet quickly is recommended, as starchy foods like rice, cereals, and crackers are easily digested and provide calories.
Parents should seek immediate medical care if their child shows any signs of severe dehydration, such as not drinking, being extremely lethargic, or having cold and pale skin.
When to Contact a Doctor
Other warning signs that require contacting a physician include:
- The presence of blood or pus in the stool, suggesting a more serious infection or condition.
- A fever that lasts longer than 48 hours.
- Diarrhea that persists beyond seven days.
- Vomiting that is green in color (suggesting bile).
- Vomiting that continues for more than 12 to 24 hours.