Stool varies with age and feeding, and a small amount of mucus may have several explanations. Because infants and young children can dehydrate quickly, call a child’s clinician for new mucus with diarrhea, blood, fever, vomiting, poor feeding, pain, unusual sleepiness, or fewer wet diapers.
Why age and feeding matter
Newborn, breastfed, formula-fed, and weaning stools naturally differ in color and texture. A caregiver’s description of the child’s age, feeding, usual stool, and what changed is more useful than matching an online photo.
Call for medical advice
- Blood, redcurrant-jelly-like stool, or black stool
- Frequent watery diarrhea
- Fever, repeated vomiting, or a swollen or painful abdomen
- Poor feeding, unusual drowsiness, or marked irritability
- Fewer wet diapers, no tears, dry mouth, sunken eyes, or other dehydration signs
- Symptoms in a newborn or young infant
Do not self-treat diarrhea
Over-the-counter anti-diarrheal medicines are generally not recommended for infants or children without clinical advice, especially when there is blood or fever. Fluid needs and the correct rehydration product depend on age and severity.
What the clinician may ask
Be ready to report stool frequency, mucus and blood, temperature, vomiting, wet diapers or urination, feeding, recent antibiotics, sick contacts, travel, growth, and how alert the child seems. A stool or blood test is used only when the history makes it useful.
Sources
We prioritize public-health agencies and established clinical institutions. Accessed August 19, 2026.
- Symptoms & Causes of Chronic Diarrhea in Children — NIDDK
- Diarrhea: When to see a doctor — Mayo Clinic