Heat Intolerance: Causes, Related Conditions, and What to Do

When the temperature rises and you feel like you’re melting while others are fine, you might be dealing with heat intolerance, a condition where your body struggles to regulate temperature in warm environments. It’s not just about being sensitive to the sun—it’s your internal thermostat acting up, often because something deeper is going on. People with heat intolerance sweat too much, feel dizzy, or get exhausted way faster than others—even in mild warmth. It’s not normal to need air conditioning in 70-degree weather, and if this sounds familiar, you’re not alone.

Hyperthyroidism, a condition where the thyroid gland produces too much hormone is one of the most common causes. That extra hormone speeds up your metabolism, turning your body into a furnace. Medication side effects, especially from antidepressants, stimulants, or beta-blockers can also throw off your temperature control. Even autonomic nervous system, the part of your nervous system that handles automatic functions like heart rate and sweating disorders can make you overreact to heat. These aren’t random symptoms—they’re signals your body sends when something needs attention.

Heat intolerance doesn’t just make you uncomfortable—it can lead to heat exhaustion or worse if ignored. If you’ve been feeling unusually hot, tired, or sweaty without obvious reason, it’s worth connecting the dots. Some people discover they have thyroid issues only after noticing they can’t handle summer anymore. Others realize their meds are the culprit after switching to a different one. The key is recognizing it’s not just "being sensitive"—it’s a clue.

Below, you’ll find real-world guides that dig into how medications, hormonal imbalances, and other hidden factors can trigger heat intolerance. You’ll learn what tests to ask for, which drugs might be making it worse, and how to manage daily life when your body just won’t cool down. No fluff. Just clear, practical info to help you figure out what’s really going on—and what to do next.