Antihypertensive medications modulate vascular tone, overall autonomic balance, and skin blood flow, thereby attenuating heat dissipation and increasing core body temperature (CBT) in people with treated hypertension. We tested the hypothesis that average CBT would be significantly higher in people with medicated hypertension across the 24-hour cycle, with a higher impairment during the night in the absence of sleep. Further work is needed to confirm these results and to determine the underlying mechanisms affecting the circadian rhythms of thermoregulation.