Side effects of amoxicillin in an infant

Amoxicillin is an antibiotic that belongs to a class of medications known as the penicillins. These drugs work by stopping bacteria from multiplying. Amoxicillin is often prescribed to infants to treat middle ear and other bacterial infections.

Although antibiotics are only effective in fighting bacterial infections and cannot relieve the symptoms caused by a viral infection, amoxicillin is used to treat different kinds of infections. Like other prescription drugs, amoxicillin has possible side effects when given to infants.

Common Side Effects

Vomiting, diarrhoea, stomach pain and skin rash are common side effects of amoxicillin. Infants often experience these symptoms when taking the drug. Feeding an infant a soy-based formula when taking a course of antibiotic treatment can help to alleviate gastrointestinal distress. If a baby develops a skin rash, this may be a sign of an allergic reaction to the drug. Discontinue use and contact your child's paediatrician. Hives and trouble breathing can be signs of a serious allergic reaction, in which case you should immediately seek emergency medical care for your infant.

Serious Side Effects

Not urinating, pale skin tone or jaundice, seizures, bloody diarrhoea and unusual bruising are more serious side effects of amoxicillin. If you are uncertain about any side effects that your baby might be experiencing, contact her paediatrician immediately. It is best to err on the side of caution since some children suffer severe allergic reactions to amoxicillin and other penicillins.

Dental Fluorosis

The findings of a study published in the October 2005 issue of the Archives of Pediatric and Adolescent Medicine suggests that giving amoxicillin to infants can damage the enamel on their permanent teeth when they erupt. Researchers found that infants who were given the antibiotic to treat bacterial infections had an increased risk of developing dental fluorosis, a condition that causes tooth enamel to become porous, staining teeth. According to the American Dental Association, dental fluorosis affects the enamel of permanent teeth while they are developing. The enamel of a child's permanent teeth continues to form from the time a baby is born until 5 or 6 years of age when the permanent teeth finally begin to come in after the loss of the baby teeth. The effects of dental fluorosis do not become obvious until that time.


Be sure to tell your child's doctor about any allergies to medication. Let the doctor know if your baby has asthma or other allergies, or a history of diarrhoea when taking antibiotics. The dose may have to be adjusted. Administer doses of amoxicillin exactly as directed by a physician or pharmacist, and according to the directions on the prescription label. Shake the liquid well before measuring the correct dose. Use a medicine cup. Place the medicine directly on your baby's tongue or mix it in formula or juice. Do not give your child any over-the-counter medications, including infant vitamin supplements while you are giving her amoxicillin unless you check first with her paediatrician to find out about any possible drug interactions. Give your baby the full course of the medication as prescribed to prevent the infection from returning.

Treating Side Effects

If your child has an upset stomach from taking amoxicillin, try giving it to him on an empty stomach. Give your baby plenty of liquids to replace fluids lost through diarrhoea and vomiting. Infants can dehydrate quickly. Therefore, watch your baby carefully if she experiences side effects from the medication. Signs that your infant may be dehydrating include dry lips, going more than six hours without a wet diaper, shedding no tears when she cries, or if she appears lethargic. Make sure your baby gets plenty of rest so that he can recover from the initial infection and any side effects caused by the medication.


Contact your baby's paediatrician if her symptoms persist after several days of treatment with the amoxicillin. Also report any side effects such as vomiting and/or diarrhoea, which continue or become more severe. Do not give your baby any medicine to treat the diarrhoea unless her paediatrician instructs you to do so.