Why do energy drinks make me tired instead of energized?
Susan Carter, MD: Endocrinologist & Longevity expert
Nov 21, 2025 · 12 min read
If you keep asking “why do energy drinks make me tired” after every can of Red Bull or Monster, the answer is rarely just “caffeine.” It is usually a mix of brain chemistry, blood sugar swings, sleep disruption, and how often you reach for those cans in the first place. “When patients ask me ‘why […]