From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Tapering off levothyroxine should only be done under medical supervision, as this medication treats hypothyroidism, a condition that typically requires lifelong treatment. If discontinuation is medically necessary, your doctor will likely reduce your dose gradually over several weeks to months, typically decreasing by 25-50 mcg every 4-6 weeks while monitoring thyroid function tests, as suggested by a study published in 2020 1. For example, if you're taking 100 mcg daily, your doctor might reduce it to 75 mcg daily for 4-6 weeks, then to 50 mcg, and so on until completely discontinued. During this process, regular blood tests to check TSH and T4 levels are essential to ensure your thyroid function remains stable, as emphasized in a study from 2019 2. Abrupt discontinuation can lead to severe hypothyroidism symptoms including fatigue, weight gain, depression, and in extreme cases, myxedema coma. The tapering approach allows your body to adjust gradually to decreasing levels of thyroid hormone and gives your natural thyroid function (if present) time to compensate. Some patients may not be candidates for complete discontinuation if they have had their thyroid removed or have permanent thyroid damage. A systematic review and meta-analysis published in 2021 found that approximately a third of patients remained euthyroid after thyroid hormone discontinuation, with a higher proportion of patients with an initial diagnosis of subclinical hypothyroidism remaining euthyroid than patients with an initial diagnosis of overt hypothyroidism 3. Key factors predicting successful discontinuation include shorter duration of levothyroxine therapy and lower maintenance dose at the time of tapering, as identified in a study from 2020 1. It is crucial to follow a systematic approach to tapering, considering individual patient factors and closely monitoring thyroid function to minimize the risk of adverse outcomes. In clinical practice, the decision to taper off levothyroxine should be made on a case-by-case basis, taking into account the patient's specific condition, medical history, and potential risks and benefits, as highlighted in a study from 2019 4. Ultimately, the goal of tapering levothyroxine is to balance the need to minimize medication use with the need to maintain optimal thyroid function and prevent hypothyroidism symptoms.