From the Guidelines
Tirosint is a better choice for patients with hypothyroidism due to its improved absorption and fewer inactive ingredients, which can lead to better treatment outcomes and reduced risk of adverse effects 1. When considering the treatment of hypothyroidism, it is essential to weigh the benefits and harms of different medications. Tirosint and Synthroid are both levothyroxine medications, but they have distinct differences. Tirosint is a liquid-filled gel capsule that improves absorption, making it a better option for patients with absorption issues, digestive conditions, or those taking medications that interfere with levothyroxine absorption. Some key points to consider when choosing between Tirosint and Synthroid include:
- Absorption issues: Tirosint may be a better choice for patients with absorption issues due to its improved absorption characteristics 1.
- Cost considerations: Synthroid is typically less expensive and more widely prescribed, making it the standard first-line treatment for many patients.
- Medication sensitivities: Tirosint contains fewer inactive ingredients, which can be beneficial for patients with sensitivities or allergies to certain ingredients.
- Insurance coverage: The choice between Tirosint and Synthroid may also depend on individual insurance coverage and out-of-pocket costs. Regular monitoring of thyroid function tests is crucial when taking either medication, and dosing should be highly individualized and adjusted by a healthcare provider as needed. While Synthroid is a common treatment option, Tirosint may be a better choice for patients who experience persistent symptoms on Synthroid despite normal lab values, due to its improved absorption and reduced risk of adverse effects 1.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Tirosint vs Synthroid
- Tirosint and Synthroid are both levothyroxine (LT4) medications used to treat hypothyroidism, but they have different formulations.
- Tirosint is a soft gel capsule formulation of LT4, while Synthroid is a traditional tablet formulation 2, 3.
- The soft gel capsule formulation of Tirosint may be more suitable for patients with gastric disorders, malabsorption, or drug interference, as it can improve bioavailability and reduce the need for frequent dose adjustments 2, 3.
- However, the evidence in favor of using Tirosint over Synthroid is weak, and additional studies are needed to investigate the potential benefits and cost-effectiveness of the soft gel capsule formulation 3.
Liothyronine (T3) Use in Hypothyroidism
- Liothyronine (T3) is sometimes used in combination with LT4 to treat hypothyroidism, particularly in patients with persistent symptoms despite achieving target TSH levels 4, 5.
- The use of T3 in hypothyroidism is controversial, and numerous randomized trials have failed to show a benefit of combination therapy over LT4 monotherapy 5.
- However, some patients with confirmed overt hypothyroidism and persistent symptoms may benefit from a trial of T3/LT4 combined therapy, and the decision to start treatment with T3 should be a shared decision between the patient and clinician 5.
Treatment of Hypothyroidism
- The goal of treatment for hypothyroidism is to normalize signs and symptoms, as well as to achieve TSH concentrations within the reference range, on an individual basis 4.
- Levothyroxine (LT4) is the standard treatment for hypothyroidism, and the dose should be optimized to achieve a TSH level within the target range 5.
- In some patients, it may be acceptable to have a serum TSH level below the reference range, but not fully suppressed in the long term 5.