We report the first case in a preterm infant given oral sulindac for treatment of symptomatic patent ductus arteriosus who subsequently developed severe acute haemorrhagic gastritis leading to disseminated intravascular coagulation, massive pulmonary haemorrhage and death. The postmortem examination suggested that the mechanism was likely a direct irritant insult causing ischaemia on the gastric mucosa. Although sulindac is supposed to be a renal-sparing non-steroidal anti-inflammatory prodrug associated with minimal renal and gastrointestinal adverse effects, clinicians should be alerted to this potential life-threatening complication in preterm infants. Until the question of safety could be adequately addressed, the use of sulindac for ductal closure should remain experimental.