From the FDA Drug Label
Thyroid hormone drugs are indicated: As replacement or supplemental therapy in patients with hypothyroidism of any etiology, except transient hypothyroidism during the recovery phase of subacute thyroiditis This category includes cretinism, myxedema and ordinary hypothyroidism in patients of any age (pediatric patients, adults, the elderly), or state (including pregnancy); primary hypothyroidism resulting from functional deficiency, primary atrophy, partial or total absence of thyroid gland, or the effects of surgery, radiation, or drugs, with or without the presence of goiter; Levothyroxine sodium is indicated in patients from birth to less than 17 years of age: • As a replacement therapy in primary (thyroidal), secondary (pituitary), and tertiary (hypothalamic) congenital or acquired hypothyroidism.
The treatment for hypothyroidism (low Thyroid-Stimulating Hormone (TSH)) in a person with no thyroid gland is replacement therapy with thyroid hormone drugs, such as levothyroxine or liothyronine 1 2.
- Key points:
- Replacement therapy is indicated for primary hypothyroidism resulting from partial or total absence of the thyroid gland.
- Levothyroxine sodium is a synthetic crystalline L-3’,5’-tetraiodothyronine sodium salt, which is chemically identical to that produced in the human thyroid gland.
- The dosage of levothyroxine sodium should be adjusted based on the patient's medical status and serum TSH levels.
From the Research
For a person without a thyroid gland, the treatment for hypothyroidism should be focused on achieving a normal TSH level, typically between 0.5-2.5 mIU/L, through levothyroxine (T4) replacement therapy, with a starting dose based on the patient's weight and gradually adjusted as needed, as recommended by the most recent study 3. The goal of treatment is to restore euthyroidism, which can be achieved with levothyroxine monotherapy, as it is the current standard for management of primary and central hypothyroidism 4. Some key points to consider in the treatment of hypothyroidism in a person without a thyroid gland include:
- The dose of levothyroxine should be adjusted based on the patient's TSH level, with the goal of achieving a normal range 4.
- The treatment should be monitored with serum TSH, with a target of 0.5-2.0 mIU/L for most adults without a thyroid gland 4.
- Medication should be taken consistently, on an empty stomach, 30-60 minutes before breakfast or 3-4 hours after the last meal of the day, and separated from medications or supplements containing calcium, iron, or aluminum by at least 4 hours.
- Combination therapy with LT4+LT3 can be considered for patients who remain symptomatic on LT4 therapy, but this should be done on a trial basis and under close monitoring, as recommended by the study 3. It's also important to note that the normal thyroid gland secretes both levothyroxine (L-T4) and levotriiodothyronine (L-T3), but the standard treatment of hypothyroidism consists of thyroxine (T4) administration alone, which may not result in a normal serum free T3 concentration, as suggested by the study 5. However, the most recent and highest quality study 3 provides the best guidance for the treatment of hypothyroidism in a person without a thyroid gland, and its recommendations should be followed.