Researchers said the drugs may alter gut bacteria, making a child more susceptible to weight gain.
The composition of gut bacteria (the microbiome) has been linked to various aspects of human health, including obesity.
Prescription of antibiotics and acid-suppressing medications in early childhood is associated with an increased risk for obesity, according to a study published online October 30 in Gut.More news: Bills sign QB Matt Barkley, re-sign P Colton Schmidt
Speaking about it, Dr Cade Nylund from the University of the Health Sciences in Maryland, senior author of the study said that there are too many unnecessary antibiotics being prescribed to infants who may not need them, for things like common colds.
Of the total group, 72.5 per cent were prescribed antibiotics, 12 per cent were prescribed H2RA acid suppressants and 3 per cent were prescribed PPI gastric protector medication.
Some 46,993 (just over 14%) children became obese, of whom 9628 (11%) had not been prescribed any antibiotics or acid suppressants.
Acid suppressants were also associated with a heightened obesity risk, although to a lesser extent, and this association strengthened for each 30-day supply prescribed. This risk increases if the child is prescribed several types of antibiotics.More news: Where to find and play Fortnite's sheet music
Because the study is observational it can not establish cause but the authors wrote: "We found that outpatient prescriptions for antibiotics and acid-suppressing medications within the first two years of life are associated with the development of early childhood obesity".
And the researchers emphasise that the links between the individual, the environment, and obesity are complex, highlighting the "current difficulty of drawing clear conclusions about the interplay between exposure history, gut microbiota and propensity to develop obesity".
He added: 'That said, childhood obesity levels in the United Kingdom are at crisis point with one in three children overweight or obese by the time they leave primary school'.More news: Thousands evacuated as Typhoon Yutu batters N. Philippines