Although the findings are concerning, researchers remained adamant they are no cause for alarm because the increased risk is minimal.
The risk of cancer was visible after five to ten years of taking antibiotics, but the team also observed a statistically significant increase in the risk after a single course of antibiotics.
The study used data from more than 40,00 patients registered at the Swedish Colorectal Cancer Registry between 2010 and 2016. It also focussed on orally administered antibiotics, as opposed to ones administered intravenously.
Colorectal cancer, also known as colon cancer, is characterised by abdominal pain and unusual changes in bowel movements.
The authors of the study also investigated a non-antibiotic drug used to treat urinary infections, to help understand how antibiotics may affect the risk of cancer.