Hypothyroidism — a condition in which your thyroid gland doesn't produce enough thyroid hormone — is an uncommon cause of peripheral neuropathy.

Peripheral neuropathy is damage to your peripheral nerves — the nerves that carry information to and from your brain and spinal cord (central nervous system) and the rest of your body, such as your arms and legs.

Peripheral neuropathy may be caused by severe, long-term, untreated hypothyroidism. Although the association between hypothyroidism and peripheral neuropathy isn't fully understood, it's known that hypothyroidism can cause fluid retention resulting in swollen tissues that exert pressure on peripheral nerves.

One of the more common areas this occurs in is the wrists, because the nerve serving the hands goes through a "tunnel" of soft tissue, which can swell, pressing on the nerve, resulting in carpal tunnel syndrome. The vast majority of carpal tunnel syndrome cases are not due to hypothyroidism, but this would be the most likely area for this to occur with hypothyroidism.

Signs and symptoms of peripheral neuropathy may include pain, a burning sensation, or numbness and tingling in the area affected by the nerve damage. It may also cause muscle weakness or loss of muscle control.

See your doctor if you know or suspect you have hypothyroidism and you're having troubling or painful symptoms in your limbs.

Treatment

Treatment of peripheral neuropathy due to hypothyroidism is directed at managing the underlying hypothyroidism and treating the resulting symptoms. This may include:

• Levothyroxine (Synthroid, Unithroid, others), which is a medication for hypothyroidism that often improves the symptoms of neuropathy
• Exercising and maintaining a healthy weight, which can help minimize stress on your body as well as strengthen affected limbs