Antibiotics are products of living simple organisms used as medicines to kill or stop the growth of bacteria infecting a living organism. Properly used, they saved many lives and prevented many serious complications. However, antibiotics have no impact on viral infections and non infectious disease. One of the common important decisions made daily by every pediatrician is whether a child's infection is viral or bacterial. Parents may learn the reasons behind some of these decisions themselves to facilitate the care of their children.

Viruses cause most infections in children:

•    Most (90%) fevers.                                                                  •    All colds.
•    Most (90%) diarrhea and vomiting.
•    Most (80%) coughs.
•    Most (80%) sore throats.
•    Most cases of croup.

Do not rely on one symptom as an indicator of bacterial infection but evaluate it as part of the whole clinical picture. Yellow nasal discharge or sputum may be observed during recovery from a cold or bronchitis respectively. High fevers may be due to a virus or bacteria. On the other hand, bacterial infection may be present without fever.

Paradoxically, starting children with colds on antibiotics early hoping to prevent progression of the infection into a bacterial one is not right. In most cases the antibiotic does not prevent but rather selects out a resistant germ to cause the secondary bacterial infection if it is due.

All medications have side effects and this includes antibiotics. Some children taking antibiotics develop diarrhea, nausea, vomiting, or a rash. If a rash occurs, it is difficult to know if it is a drug allergy or an unrelated rash. Stopping the antibiotic is commonly advised and many children are mislabeled as allergic to a family of antibiotics. Thus, a potentially useful antibiotic is not available when the child really needs it.