Melatonin-induced symptomatic bradycardia in an otherwise healthy male: a case report.

Melatonin, a pineal gland hormone closely associated with the circadian rhythm, has been trending over the past years as an over-the-counter medication to aid with sleep disturbances. Although generally believed to be safe, recent studies show negative inotropic and chronotropic effects on the heart rate and blood pressure in humans. Several studies suggested that melatonin induces cardiac vagal tone and affects heart rate and mean arterial pressure.

Acute massive posterior stroke with tonsillar herniation in a scuba diver.

A transient female passenger in her 40s presented to the emergency department (ED) exhibiting drowsiness post-scuba diving. Despite normal initial vitals, she reported dizziness, sleepiness, and occipital headache. A computed tomography (CT) scan showed a severe posterior circulation acute infarction affecting various brain regions, resulting in significant mass effects and complications like 4th ventricle compression, cerebellar tonsillar herniation, and hydrocephalus.