The Stool Reducing Sugar test is a specialized, non-invasive test used primarily for infants and young children. It is the key diagnostic tool for investigating persistent diarrhea, gas, and bloating in a child. The test checks for the presence of unabsorbed sugars (like lactose) in a stool sample. This is the gold-standard method for diagnosing lactose intolerance or other carbohydrate malabsorption issues in children. This simple, painless stool test provides a clear, fast, and non-invasive answer, helping your pediatrician find the root cause of your child's discomfort and get them on the right path to relief.