Dangers of Antibiotics for Children

Do you really need to give your child antibiotics for them to beat the flu and a bout of the sniffles? When it comes to antibiotics, parents are indeed faced with a tough choice, especially when there is plenty of research that links the use of antibiotics in early childhood with both short and long-term implications.

There is compelling evidence that use of antibiotics in early life sets your kid up for an increased risk of developing asthma, allergies, anxiety, obesity and inflammatory bowel disease down the road not to mention increased risk of drug resistant infections, considered as one of the biggest health threats facing the world today.

How antibiotics affect your kid’s health?

The answer lies in the gut microbiota – a community of both good (health boosting) and bad (disease-causing) microbes living in the intestines. Your gut is home to trillions of microorganisms that play some critical functions in keeping your body healthy and free of disease. These microbes, for example, help in digestion, absorption of nutrients and production of vitamins. These tiny residents of your gut also release molecules that train your immune cells to work efficiently.

Antibiotics just don’t have the ability to distinguish between healthy microorganisms and the ones that make you sick. They kill indiscriminately, and this changes the natural composition and the diversity (richness of bacterial species) of intestinal microbiota. This kind of negative shift increases the risk of developing all types of chronic illnesses. Children, who are prescribed a significantly high number of antibiotics in primary care, are especially vulnerable to these negative side effects.  

What makes kids more vulnerable? Well, it generally takes the first three to five years of life for a child’s gut microbiome to develop fully as a community. In early life, the gut flora plays a critical role in kick-starting a child’s immune system and in programming their metabolism. The use of antibiotics in early childhood impairs this important development.

Obviously, the use of antibiotics early in life, when a child’s microbiota is underdeveloped and at its most vulnerable, can compromise immune and metabolic health, increasing the risk of health problems later in life. In fact, when given to breastfeeding babies, antibiotics may even dilute some of the health benefits of gained from long duration breastfeeding, such as reduced frequency of infections and reduced risk of being overweight. [1]

Worse yet, a study published in Nature Communications showed that a child’s gut flora may take at least a year or sometimes up to two years to fully recover from the damage caused by some antibiotics, especially those that are used to treat upper respiratory tract infections. The study revealed that “macrolide use in childhood is associated with long-term distortions in the composition, function and antibiotic resistance of the intestinal microbiota.” It also reported that kids who received antibiotics, especially macrolides like azithromycin, in the first two years of life are more likely to be obese and develop asthma later in life. [2]

Interestingly, scientists are now investigating whether a squeaky-clean environment (excessive use of sanitizers and less exposure to dirt) and the use of antibiotics early in life could be a possible link between abnormal gut composition and increased rates of asthma, allergies and even autism spectrum disorder.

Let’s look at how this ‘altered gut microbiota’ spills into a number of serious health complications for your child.

1.    Increased risk of drug-resistant infections

Frequent exposure to antibiotics appears to be an important player in the development of drug-resistance infections in children. What this means is that the current crop of antibiotics is becoming less and less effective at overcoming infections. This is giving rise to superbugs – strains of bacteria that are resistant to different types of antibiotics. Drug resistant infections last longer, are difficult to treat and they are more likely to cause serious complications that may require hospitalization.

What is worrying is that even a single course of antibiotics can contribute to resistant infections. And this resistance can persist up to several months after treatment. A growing pool of research confirms this.

A 2016 meta-analysis found that kids who were given antibiotics for urinary tract infections (caused by E coli) were several times more likely to develop a resistant infection in the following six months, than kids who were not given antibiotics. [3]

And this risk is not limited to kids who are administered antibiotics directly. Even babies born to mothers who take antibiotics during pregnancy are at an increased risk. A new study by the Murdoch Children’s Research Institute (MCRI) found that children born to mothers who took antibiotics before or during pregnancy were up for an increased risk of childhood infections that required hospital treatment. Those born vaginally were at greater risk than caesarean kids. And this risk was particularly higher for gastrointestinal infections and when antibiotics were taken closer to the delivery date. [4]

Again, this higher risk of infections in children is attributed to the reduced number of good bacteria in the mother’s gut flora. During vaginal births, babies acquire their microbiota legacy through the mother’s gut and birth canal, which helps them kick start their immune development. Antibiotics during pregnancy affects the bacterial make-up in the mother’s gut, which is then passed on to the baby. This impacts their immune growth, leaving them an easy target for opportunistic infections in early childhood. However, babies born through caesarean sections pick their microbiota from their mother’s skin and hospital environment.   

Researchers were quick to add, however, that it is important for women to take antibiotics for certain infections, such as urinary tract infections or if they need to undergo any surgical procedure during pregnancy. But the fact remains, this could have serious, long-term repercussions for both mothers and their babies and there is a need to investigate if giving probiotics can lower the risks.  

2.    Increased risk of asthma and allergies

Oral antibiotics are commonly and frequently used to treat respiratory tract infections in children. Ironically, this further increases the risk of developing childhood asthma and allergies in kids.

A 2017 study published in the journal ‘Pediatric Allergy and Immunology’ concluded that “children treated with antibiotic in the first 3 years of life are more likely to develop asthma.” [5]

The findings from this 2017 Japanese study also concluded that use of antibiotics within the first 2 years of life may increase the risk for “current asthma, current atopic dermatitis, and current allergic rhinitis in 5-year-old children.” [6]
A 2015 meta-analysis suggested that use of antibiotics during pregnancy is likely to increase the risk of wheeze/asthma in childhood. [7]

3.    Increased risk of obesity in children

A number of studies have linked repeated exposure to antibiotics in children with risk of obesity in early childhood, which is a serious problem at so many levels. It can lead to depression in children and affect their academic performance. It also increases their chance of being obese as they grow up and increases the risk of developing type 2 diabetes, cardiovascular diseases and even cancer.  

A 2016 study published in ‘Gastroenterology’ found that taking 3 or more courses of antibiotics before the age of 2 years increases risk of early childhood obesity. [8] A meta-analysis of fifteen cohort studies also provided strong evidence for the role that antibiotics use plays in early life on childhood obesity and overweight risk. [9]
An important study published in the journal ‘Microbiome’ revealed that the gut microbiota of infants may serve as an early indicator of obesity risk. [10]. The researchers from this study also previously reported that early-life use of macrolide antibiotics increases the risk of obesity and lowers the beneficial effects of breastfeeding.

One possible theory that explains this association is the ‘altered composition of gut microbiota’. Use of these drugs bring a negative shift in the gut microbiome – such as low diversity in bacterial species and reduced amounts of beneficial bacteria (such as Bifidobacterium) that play an important role in energy metabolism and reducing inflammation.

These changes so early in life are not only linked with poor immune development in children but also with impaired glucose and fat metabolism. This partly explains how frequent use of antibiotics can contribute to obesity and metabolic disorders in children (and in adults).

To give or not to give?

There is no denying that antibiotics can save lives from certain infections that can indeed be deadly. But these drugs are not effective against all kinds of infections. Here is what you should know before you give your child an antibiotic in the hope of providing immediate relief.  Antibiotics are only good at treating or preventing some types of bacterial infections. They are ineffective against viral infections such as the common cold, flu, most coughs, and sore throats.

It is feared that overuse of antibiotics, especially to treat infections that don’t require such therapy, may give rise to stubborn infections that won’t be treated at all with any of the antibiotics that we have available to us today. There lurks a very real danger that we might revert back to a time when even a small infection had the potential to kill.  


  1. Korpela, K. et al. Association of Early-Life Antibiotic Use and Protective Effects of Breastfeeding: Role of the Intestinal Microbiota. JAMA Pediatr. 2016
  2. Korpela, K. et al. Intestinal microbiome is related to lifetime antibiotic use in Finnish pre-school children. Nat. Commun. 2016
  3. Bryce Ashley, Hay Alastair D, Lane Isabel F, Thornton Hannah V, Wootton Mandy, Costelloe Céire et al. Global prevalence of antibiotic resistance in paediatric urinary tract infections caused by Escherichia coli and association with routine use of antibiotics in primary care: systematic review and meta-analysis. BMJ 2016; 352 :i939
  4. https://academic.oup.com/ije/advance-article-abstract/doi/10.1093/ije/dyx272/4833213?redirectedFrom=fulltext
  5. Ahmadizar et al. Early life antibiotic use and the risk of asthma and asthma exacerbations in children. Pediatr Allergy Immunol. 2017
  6. Yamamoto et al. Influence of antibiotic use in early childhood on asthma and allergic diseases at age 5. Annals of Allergy, Asthma & Immunology. 2017.
  7. Zhao et al. Prenatal antibiotic use and risk of childhood wheeze/asthma: A meta-analysis. Pediatr Allergy Immunol. 2015
  8. Scott eat al. Administration of Antibiotics to Children Before Age 2 Years Increases Risk for Childhood Obesity. Gastroenterology. 2016.
  9. Shao et al. Antibiotic Exposure in Early Life Increases Risk of Childhood Obesity: A Systematic Review and Meta-Analysis. Front. Endocrinol. 2017.
  10. Korpela et al. Childhood BMI in relation to microbiota in infancy and lifetime antibiotic use. Microbiome 2017.