From the Research
Routine thyroid function testing is not typically required before starting Plaquenil (hydroxychloroquine). There is no established recommendation to check thyroid function specifically as part of the pre-treatment screening for Plaquenil therapy. The standard pre-treatment assessments for Plaquenil include a comprehensive eye examination, complete blood count, liver function tests, and renal function tests. Plaquenil does not have direct effects on thyroid function that would necessitate routine thyroid screening. However, if a patient has pre-existing thyroid disease or symptoms suggestive of thyroid dysfunction (such as unexplained fatigue, weight changes, or temperature intolerance), thyroid function testing would be appropriate as part of their overall medical care. Additionally, since Plaquenil is often prescribed for autoimmune conditions like lupus or rheumatoid arthritis, and these conditions can have associations with autoimmune thyroid disorders, clinicians might consider thyroid testing based on individual patient factors rather than as a standard requirement for Plaquenil initiation 1.
Some studies have investigated the relationship between thyroid function and various treatments, but these do not directly apply to the initiation of Plaquenil therapy. For example, a study on immunotherapy found that baseline serum TSH levels can predict the absence of thyroid dysfunction in cancer patients treated with immunotherapy 2. Another study found that growth hormone replacement therapy can affect thyroid function in adults with growth hormone deficiency, but this is not relevant to Plaquenil therapy 3. The American Thyroid Association has also published guidelines for the treatment of hypothyroidism, which emphasize the importance of individualized clinical judgment and do not address Plaquenil therapy specifically 4.
In terms of patient care, it is essential to prioritize morbidity, mortality, and quality of life when making decisions about thyroid function testing. If a patient has symptoms or a history suggestive of thyroid dysfunction, testing may be warranted, regardless of the planned initiation of Plaquenil therapy. However, routine testing is not necessary for all patients starting Plaquenil. The most recent and highest-quality studies do not support routine thyroid function testing as a standard requirement for Plaquenil initiation 1, 2.
Key points to consider:
- Plaquenil does not have direct effects on thyroid function that would necessitate routine thyroid screening.
- Pre-existing thyroid disease or symptoms suggestive of thyroid dysfunction may warrant thyroid function testing.
- Autoimmune conditions like lupus or rheumatoid arthritis may have associations with autoimmune thyroid disorders, and clinicians may consider thyroid testing based on individual patient factors.
- Routine thyroid function testing is not typically required before starting Plaquenil.