Fever with vomiting in infants

Fever with vomiting in infants: When to see a doctor

The combination of high fever and vomiting in an infant is always a reason for close attention from parents. This symptom combination can indicate a variety of illnesses, from a common viral infection to more serious conditions. The main danger this tandem carries is the risk of rapid dehydration, which develops much faster in infants than in adults.

Most common causes of fever and vomiting

• Gastroenteritis (intestinal infection). This is the number one cause. Most often caused by viruses (rotavirus, norovirus). In addition to fever and vomiting, diarrhea, abdominal pain and poor appetite are usually observed.
• Systemic infections. Many infections not directly related to the stomach can cause vomiting with high fever. This can be otitis (ear infection), a urinary tract infection, or even pneumonia.
• Food poisoning. Although it occurs less often in infants, consumption of poor‑quality formula or complementary foods can trigger such a reaction.
• High fever itself. Sometimes a very high fever can provoke a vomiting reflex even without primary gastrointestinal involvement.

Parents' main task: Preventing dehydration

During vomiting the body loses not only water but also important electrolytes. Therefore your key task is not to force‑feed the child at any cost, but to ensure adequate fluid replacement.

• Frequent small sips. Offer the child breast, formula, or special rehydration solutions (for children older than 6 months, after consulting a doctor) in very small amounts (5‑10 ml) but very often (every 5‑10 minutes). A large volume of fluid taken at once can trigger another vomiting episode.

When is immediate medical assistance needed?

Seek medical attention immediately if:

• The child refuses any fluid.
• Signs of dehydration are observed (dry diapers, absence of tears, sunken fontanelle).
• Vomiting is relentless or "projectile".
• Vomitus contains blood or bile (green color).
• The child is very lethargic or, conversely, excessively agitated.

Read about how to properly reduce fever in our blog "Fever in infants: when to reduce it".