From the Guidelines
Thyroid disorders are not a common cause of pruritus, and routine endocrine investigations, including thyroid function tests, are not recommended unless additional clinical features are present. When considering the relationship between thyroid disorders and pruritus, it's essential to prioritize the most recent and highest quality evidence. According to the British Association of Dermatologists' guidelines for the investigation and management of generalized pruritus in adults without an underlying dermatosis, 2018 1, routine endocrine investigations, including thyroid function tests, are not recommended unless additional clinical features are present.
Key Points to Consider
- A study examining 220 newly diagnosed patients with thyroid disease and 90 healthy controls found that chronic nonspecific pruritus was not a common finding in the thyroid group (27%) 1.
- Another retrospective study following up 263 patients with pruritus for 3 years found only three instances of associated thyroid disease, suggesting that thyroid disease is an uncommon cause of pruritus 1.
- The British Association of Dermatologists' guidelines also state that conventional reviews and medical textbooks may overstate the association between thyroid disorders and generalized pruritus, with limited evidence to support this claim 1.
Recommendations for Management
- For patients with generalized pruritus, a thorough clinical evaluation to identify underlying causes is essential, rather than routine endocrine investigations 1.
- If thyroid disease is suspected, thyroid function tests may be considered, but only in the presence of additional clinical features 1.
- For immediate relief, fragrance-free moisturizers and lukewarm showers may help reduce itching, while over-the-counter antihistamines or topical corticosteroids may be prescribed for severe cases 1.
From the Research
Causes of Pruritus in Thyroid Disorders
- Pruritus, or itching, can be a symptom of underlying systemic disease, including thyroid disease 2
- Thyroid disorders, such as hyperthyroidism and hypothyroidism, can cause pruritus, although the exact mechanism is not fully understood
- Hashimoto thyroiditis, an autoimmune disorder, is a common cause of hypothyroidism and can be associated with pruritus 3, 4
Thyroid Disorders and Pruritus
- Hyperthyroidism can cause pruritus, and treatment of the underlying condition can help alleviate symptoms 5
- Hypothyroidism can also cause pruritus, and treatment with levothyroxine can help relieve symptoms 4, 6
- Other forms of thyroiditis, such as subacute thyroiditis, can also cause pruritus, and treatment should focus on symptoms 3
Diagnosis and Treatment
- Diagnosis of thyroid disorders involves laboratory testing, including measurement of thyroid-stimulating hormone (TSH) levels and serum free thyroxine levels 4, 6
- Treatment of thyroid disorders, such as hyperthyroidism and hypothyroidism, can help alleviate symptoms of pruritus 5, 4, 6
- Removal of the causative agent and appropriate investigation and treatment of the underlying disease are essential first-line measures in the treatment of pruritus 2