Amoxicillin side effects in infants

Updated February 21, 2017

A member of the penicillin class, amoxicillin does not kill bacteria. Rather, it prevents bacteria from multiplying by keeping them from forming their protective walls. Amoxicillin is effective against such strains of bacteria as Streptococci, H. influenzae, E. coli, N. gonorrhoea, Pneumococci and particular types of Staphylococci, because these bacteria cannot survive without their protective cellular walls. Like all medications, amoxicillin may have some side effects, particularly in infants.


Amoxicillin, often referred to as 'the pink stuff,' is frequently used to treat bacterial infections in newborns and is considered safe for use by nursing mothers. However, small amounts of amoxicillin may pass into breast milk and may result in diarrhoea in the nursing infant. A small percentage of infants are allergic to amoxicillin. If the infant displays any allergic reaction after nursing, a doctor should be contacted immediately.


Amoxicillin is frequently the antibiotic of choice for the treatment of ear infections in infants under one year old. It is one of the milder antibiotics on the market, it is inexpensive and it is generally effective. Occasionally, if the child is prone to ear infections, she may build up a resistance to amoxicillin and require a different or more potent antibiotic. In most cases the most severe side effects are diarrhoea, diaper rash, oral thrush and vomiting.


General side effects of amoxicillin that can affect anyone including infants are diarrhoea, nausea. rash, bleeding, bruising and vomiting. Additional side effects that may not be as easy to determine in infants include dizziness, heartburn, insomnia, itching, confusion and abdominal pain. Infants should be observed closely to see if any of these side effects present. If any of these side effect persist or get worse, the prescribing physician should be contacted as soon as possible.


Individuals who are allergic to any form of cephalosporin or penicillin should consult their doctor before allowing amoxicillin to be prescribed for their infant, as the allergy may be hereditary. If the antibiotic is administered and the infant exhibits any reaction, you should seek immediate medical attention. Allergic reactions to these antibiotics can be extreme and in some cases fatal. Inform the doctor if the infant has exhibited any sign of asthma, hives or other allergies prior to administering amoxicillin.


Prolonged or repeated use of amoxicillin could result in oral thrush or a vaginal fungal infection in infants. In rare instances, amoxicillin may cause pseudomembranous colitis, a severe intestinal condition which may present up to several weeks after use of the antibiotic has stopped. If symptoms appear, the physician should be contacted immediately.

Cite this Article A tool to create a citation to reference this article Cite this Article


About the Author

Mike Parker is a full-time writer, publisher and independent businessman. His background includes a career as an investments broker with such NYSE member firms as Edward Jones & Company, AG Edwards & Sons and Dean Witter. He helped launch DiscoverCard as one of the company's first merchant sales reps.