What should be done if a patient's TSH level remains elevated after 8 weeks of levothyroxine treatment?

When a patient's TSH (Thyroid Stimulating Hormone) level remains elevated after 8 weeks of levothyroxine treatment, an increase in the dose of levothyroxine is typically warranted. Levothyroxine is a synthetic form of the thyroid hormone thyroxine (T4) and is used to replace or supplement insufficient thyroid hormone levels in conditions such as hypothyroidism.

The general guideline is to re-evaluate TSH levels approximately 6 to 8 weeks after initiating or adjusting levothyroxine therapy, as it takes about that time for the body to stabilize thyroid hormone levels in response to the medication. If TSH remains elevated, it indicates that the current dose is not sufficient to achieve the desired suppression of TSH. Increasing the dose allows for greater T4 availability, which can lead to a decrease in TSH levels and help bring the patient's thyroid function back to the normal range.

It's important to note that the specific dose increase must be individualized based on the patient's response, weight, age, and any concomitant medical conditions. However, an increase in dosage is the most appropriate response when faced with persistently elevated TSH levels after a reasonable period of treatment.