β2-agonist toxicity in pregnancy causing troponin elevation and fetal distress.

β₂-agonist toxicity is a rare complication of asthma treatment, but there is little information about its interplay in pregnancy with maternal and fetal physiology. This case describes a woman in her early 30s at 37 weeks gestation with supratherapeutic use of inhaled salbutamol and salmeterol in the setting of worsening shortness of breath in the third trimester of pregnancy. She presented to the emergency department with chest discomfort and shortness of breath with a raised maternal lactate and troponin. Fetal cardiotocography was abnormal, so birth was expedited by emergency caesarean section due to concerns for fetal distress secondary to β₂-agonist toxicity. This case highlights the risks of inhaled β₂-agonist toxicity in pregnancy, which can be associated with troponin rise and fetal distress, even in the absence of a severe asthma exacerbation. It also highlights the importance of antenatal asthma education to ensure care is appropriately escalated when needed.