What to do about elevated Thyroid-Stimulating Hormone (TSH) levels, with the client taking 110 micrograms of Levothyroxine (levothyroxine)?

From the Guidelines

A TSH level of 41.0 indicates significant hypothyroidism despite the current levothyroxine dose of 110 mcg, requiring prompt dose adjustment, and I recommend increasing the levothyroxine dose by approximately 25-50 mcg (to 135-160 mcg daily). This recommendation is based on the principle of full replacement therapy, which can be estimated using ideal body weight for a dose of approximately 1.6 mcg/kg/d, as suggested by the study 1.

Key Considerations

• The patient's current dose of 110 mcg may not be sufficient to achieve a normal TSH level, and an increase in dose is necessary to alleviate symptoms of hypothyroidism.
• It is essential to consider factors that may affect levothyroxine absorption, such as taking the medication with food, calcium, iron supplements, or antacids, which can interfere with absorption.
• The patient should be advised to take levothyroxine on an empty stomach, at least 30-60 minutes before breakfast or any other medications.

Monitoring and Follow-up

• Follow-up thyroid function testing should be performed in 6-8 weeks to assess the response to the increased dose and adjust the dose as needed to achieve a TSH within the normal range (typically 0.4-4.0 mIU/L).
• The goal of treatment is to relieve symptoms of hypothyroidism, such as fatigue, cold intolerance, weight gain, and cognitive slowing, while minimizing the risk of overtreatment and potential cardiac complications, as noted in the study 1.

From the FDA Drug Label

Due to differences in absorption characteristics of patients and the oral levothyroxine product formulations, TSH and thyroid hormone levels should be measured a few weeks after initiating oral levothyroxine and dose adjusted accordingly.

The client's TSH level is 41.0 while taking 110 mcg of levothyroxin, indicating that the current dose may not be sufficient to achieve a euthyroid state.

• The dose of levothyroxin may need to be increased to achieve a normal TSH level.
• It is recommended to monitor TSH and thyroid hormone levels regularly and adjust the dose accordingly.
• The client should be closely monitored for signs of thyroid toxicity or other adverse effects. 2

From the Research

TSH Level of 41.0 and Levothyroxin Treatment

• A TSH level of 41.0 is significantly elevated, indicating hypothyroidism 3, 4.
• The client is currently taking 110 mcg of levothyroxin, which is a standard treatment for hypothyroidism 3.
• The goal of levothyroxin treatment is to normalize TSH levels, which should be between 0.4-4.0 mU/l 3.

Adjusting Levothyroxin Dosage

• The dosage of levothyroxin may need to be adjusted to achieve a normal TSH level 3, 4.
• The adjustment of levothyroxin dosage should be based on the patient's age, presence of pregnancy or comorbidities, and other factors 3.
• In general, thyroid hormone replacement therapy in non-pregnant adults ≤ 70 years is clearly indicated if the TSH concentration is >10 mU/l 3.

Combination Therapy with Levothyroxine and Liothyronine

• Combination therapy with levothyroxine and liothyronine may be considered in patients with persistence of symptoms, despite optimal levothyroxine treatment, based on expert opinion 3, 5.
• However, the use of combination therapy is still a matter of debate and not recommended as standard therapy 3, 5.
• Some studies suggest that combination therapy may be beneficial in certain patients, such as those with a polymorphism in type 2 deiodinase 4, 5.

Monitoring and Follow-up

• Regular monitoring of TSH levels is necessary to adjust the levothyroxin dosage and prevent over- or under-treatment 3, 4.
• Patients with hypothyroidism should be followed up regularly to monitor their symptoms and adjust their treatment as needed 3, 4.