# Excessive Sweating

URL: https://thethyroidologist.com/symptoms/excessive-sweating/
Section: Symptoms
Last medically reviewed: 2025-11-15

> An overactive thyroid commonly causes excessive sweating and heat intolerance. Why it happens and when to investigate.

Excessive sweating — especially with heat intolerance and a fast heart rate — is a classic feature of an overactive thyroid. The body’s thermostat runs high, and sweat production increases to lose heat.
Sweating is usually generalised rather than confined to the palms, though both patterns can occur.

## Why hyperthyroidism causes sweating

Thyroid hormone increases the basal metabolic rate and the body’s sensitivity to adrenaline. The result is more heat production and a stronger sweating response, even in cool conditions.
People often notice damp palms, sweating at night, or discomfort in warm rooms.

## Other causes

Excessive sweating is common and often unrelated to the thyroid: hot climates, exercise, anxiety, menopause, fever, diabetes and some medications can all cause it.
Focal sweating of the palms, soles or armpits may be a primary hyperhidrosis rather than a thyroid problem.

## When to investigate

Thyroid testing is reasonable when sweating accompanies weight loss, palpitations, tremor, heat intolerance, frequent bowel movements or neck swelling.
Night sweats with fever, weight loss or lymph node swelling need separate assessment.

## Management

Treating the underlying hyperthyroidism resolves the sweating in most cases. In the meantime, lightweight clothing, hydration and antiperspirants can help.

## Frequently asked questions

### Is excessive sweating a thyroid symptom?

Yes — it is a common feature of an overactive thyroid, especially when accompanied by heat intolerance, palpitations and weight loss.

### Can hypothyroidism cause sweating?

It usually causes reduced sweating and cold intolerance, not excessive sweating.

### Will treatment stop it?

Thyroid-related sweating usually improves as thyroid function is controlled, though it may take some weeks.

### What if my thyroid tests are normal?

Other causes such as anxiety, menopause or primary hyperhidrosis should be considered with your clinician.

## Disclaimer

The content on this website is for general educational purposes only and does not constitute medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional about your specific condition.

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Part of The Thyroidologist — https://thethyroidologist.com