Please confirm that an ethics committee approval has been applied for or granted: Not relevant (see information at the bottom of this page)

Background and Aims Pyrexia and shivering are the most popular side effects of postpartum administration of misoprostol. However, other side effects can be present and are very rare. We present a case of a 33-year-old post-partum woman admitted to the recovery room who presented delirium with shivering, malignant hyperthermia (MH) and tachycardia after misoprostol administration. We aim to demonstrate that although MH and cardiac dysrhythmias are very rare side effects of misoprostol administration, these should be acknowledged and not undervalued.

Methods The vaginal delivery was discotic and performed under epidural analgesia. 25 IU of oxytocin were administered right after placental removal for uterine atony prophylaxis and about 3h after, 4 rectal tablets of misoprostol (800 mcg total) were used due to uterine relaxation and mild hemorrhage. Both were controlled along with an onset of delirium, severe tachycardia (192/min) and high fever (41°C). 5mg of intravenous diazepam was administered to control the altered mental status with 1g of paracetamol and 1g of metamizole to lower the temperature. ECG results revealed sinus tachycardia.

Results She was admitted to the ICU and discharged two days later. Hemodynamic stability and euthermia were achieved 8h post misoprostol administration and a cranial CT scan showed no alterations.

Conclusions Although 800mcg of misoprostol is considered the standard dose in the last FIGO guidelines, its side effects are dose-related and even rare ones as hyperthermia should be taken into consideration in these cases, especially in deliveries under general anesthesia with volatile anesthetics or other triggers for MH.