There are no data focusing on the safety of overdose of ampicillin and pyridium during pregnancy. This study aims to report the outcome of a pregnant woman with an acute overdose of oral ampicillin+pyridium in the 14 th week of pregnancy. A 27-year-old woman was referred to Teratology Information Service with a suicide history of ingesting 28 ampicillin+pyridium (500+50 mg) tablets. A structured, evidence-based counseling regarding her exposure to overdosing was provided, and she decided to continue her pregnancy. She gave birth to a baby in the 38 th gestational week with fetal growth restriction (FGR), with no major congenital malformations and/or deformations. The follow-up of the infant in the 14 th month of her life revealed normal physical and neurodevelopmental findings. Because the mother had no major risk factors and exposure of experimental animals to this overdosage have yielded comparable results, and the FGR in this case may be attributed to medication exposure.