Strengthening pharmacovigilance: Misoprostol-induced anaphylaxis in obstetric care

Misoprostol, a prostaglandin E1 analogue, is widely used in obstetric care for the induction of labour, management of miscarriage, and postpartum haemorrhage. Adverse effects are usually mild; however, severe hypersensitivity reactions such as anaphylaxis are exceedingly rare and may qualify as maternal near-miss events. We report a 35-year-old primigravida with an in vitro fertilisation conception who presented with a missed miscarriage at 20+6 weeks of gestation. She received mifepristone and cervical priming with a Foley catheter, followed by sublingual misoprostol 400 µg. Within minutes, she developed severe anaphylaxis characterized by facial oedema, tongue swelling, respiratory distress, hypoxaemia, hypotension, and tachycardia. Immediate management with intramuscular adrenaline, high-flow oxygen, intravenous fluids, corticosteroids, antihistamines, and nebulised bronchodilators stabilised her condition. She was transferred to the intensive care unit, and uterine evacuation was subsequently completed using oxytocin infusion. She recovered uneventfully and was discharged on day 6. Adverse drug reaction assessment using the Naranjo algorithm yielded a score of 7, indicating a probable reaction. Misoprostol-induced anaphylaxis, though extremely rare, can be life-threatening. This case underscores the importance of preparedness with adrenaline, adherence to anaphylaxis management protocols, and strengthened pharmacovigilance reporting systems to enhance maternal drug safety.