# Muscle Aches and Weakness

URL: https://thethyroidologist.com/symptoms/muscle-aches-and-weakness/
Section: Symptoms
Last medically reviewed: 2025-11-15

> Muscle pain, cramps and weakness can accompany both an under- and overactive thyroid. Why it happens and when to investigate.

Muscle aches, cramps and weakness are recognised features of thyroid disease. In an underactive thyroid they tend to build slowly; in an overactive thyroid they can appear with wasting and fatigue.
Because muscle symptoms are so common in everyday life, thyroid disease is easily missed unless other clues are present.

## How hypothyroidism affects muscles

In hypothyroidism, muscles may ache, feel stiff and cramp, and the reflexes slow. Some people notice weakness, particularly in the shoulders and hips, and muscle enzymes can be mildly raised on blood tests.
These symptoms generally improve with adequate thyroid hormone replacement.

## How hyperthyroidism affects muscles

An overactive thyroid can cause muscle weakness and wasting, sometimes with difficulty climbing stairs or lifting the arms. This reflects the increased metabolic rate breaking down muscle.
The changes are usually reversible once thyroid function is controlled.

## Other causes

Muscle aches are far more often due to strain, medication side effects, vitamin D deficiency, or other conditions. Blood tests — including thyroid function, vitamin D, and muscle enzymes — help sort out the cause.
A clinician can distinguish thyroid-related muscle symptoms from other causes.

## Frequently asked questions

### Can thyroid disease cause muscle pain?

Yes — both hypothyroidism and hyperthyroidism can cause muscle aches, cramps and weakness, which usually improve when thyroid function is treated.

### Is the weakness permanent?

In most cases it is reversible once thyroid levels are corrected, though recovery can take time.

### What tests might I need?

Thyroid function tests are the starting point. Depending on the picture, vitamin D, calcium and muscle enzyme tests may also be checked.

## 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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