This study found that ranitidine use in very low birth weight newborns was associated with higher rates of infections, necrotizing enterocolitis (NEC), and mortality. Newborns treated with ranitidine had over 5 times higher risk of infections like sepsis and pneumonia compared to those not treated. Rates of NEC and mortality were also significantly higher in newborns receiving ranitidine. The study cautions against the use of ranitidine in preterm newborns due to these risks of severe infectious diseases and fatal outcomes.