U.S. flag An official website of the United States government
  1. Home
  2. Drug Databases
  3. Drug Safety-related Labeling Changes

Drug Safety-related Labeling Changes (SrLC)

Get Email Alerts | Guide

LEVO-T (NDA-021342)


Safety-related Labeling Changes Approved by FDA Center for Drug Evaluation and Research (CDER)

Download Data

Expand all

12/05/2017 (SUPPL-23)

Approved Drug Label (PDF)

Boxed Warning

PLR conversion; newly added information:


Thyroid hormones, including Levo-T, either alone or with other therapeutic agents, should not be used for the treatment of obesity or for weight loss.

In euthyroid patients, doses within the range of daily hormonal requirements are ineffective for weight reduction.

Larger doses may produce serious or even life threatening manifestations of toxicity, particularly when given in association with sympathomimetic amines such as those used for their anorectic effects.

5 Warnings and Precautions

PLR conversion created the following six subsections; please refer to label for complete information.

5.1 Cardiac Adverse Reactions in the Elderly and in Patients with Underlying Cardiovascular Disease

5.2 Myxedema Coma

5.3 Acute Adrenal Crisis in Patients with Concomitant Adrenal Insufficiency

5.4 Prevention of Hyperthyroidism or Incomplete Treatment of Hypothyroidism

5.5 Worsening of Diabetic Control

5.6 Decreased Bone Mineral Density Associated with Thyroid Hormone Over-Replacement

6 Adverse Reactions

Addition of the following:

Dermatologic: rash

Newly created subsection titles:

Adverse Reactions in Children

Pseudotumor cerebri and slipped capital femoral epiphysis …

Hypersensitivity Reactions

Hypersensitivity reactions to inactive ingredients have occurred in patients …

7 Drug Interactions

PLR conversion created the following subsections and associated tables; please refer to label for complete information.

7.1 Drugs Known to Affect Thyroid Hormone Pharmacokinetics

  • Table 2. Drugs That May Decrease T4 Absorption (Hypothyroidism)

  • Table 3. Drugs That May Alter T4 and Triiodothyronine (T3) Serum Transport Without Affecting Free Thyroxine (FT4) Concentration (Euthyroidism)

  • Table 4. Drugs That May Alter Hepatic Metabolism of T4 (Hypothyroidism)

  • Table 5. Drugs That May Decrease Conversion of T4 to T3

7.2 Antidiabetic Therapy

7.3 Oral Anticoagulants

7.4 Digitalis Glycosides

7.5 Antidepressant Therapy

7.6 Ketamine

7.7 Sympathomimetics

7.8 Tyrosine-Kinase Inhibitors

7.9 Drug-Food Interactions

7.10 Drug-Laboratory Test Interactions

8 Use in Specific Populations

Newly created sections by PLR conversion; please refer to label for complete information.

8.1 Pregnancy

8.2 Lactation

8.4 Pediatric Use

8.5 Geriatric Use

17 PCI/PI/MG (Patient Counseling Information/Patient Information/Medication Guide)


Newly created section by PLR conversion;

Inform the patient of the following information to aid in the safe and effective use of LEVO-T:

Dosing and Administration

  • Instruct patients that LEVO-T should be taken with a full glass of water since the tablet may rapidly disintegrate.

  • Instruct patients to take LEVO-T only as directed by their healthcare provider.

  • Instruct patients to take LEVO-T as a single dose, preferably on an empty stomach, one-half to one hour before breakfast.

  • Inform patients that agents such as iron and calcium supplements and antacids can decrease the absorption of levothyroxine. Instruct patients not to take LEVO-T tablets within 4 hours of these agents.

  • Instruct patients to notify their healthcare provider if they are pregnant or breastfeeding or are thinking of becoming pregnant while taking LEVO-T.

Important Information

  • Inform patients that it may take several weeks before they notice an improvement in symptoms.

  • Inform patients that the levothyroxine in LEVO-T is intended to replace a hormone that is normally produced by the thyroid gland. Generally, replacement therapy is to be taken for life.

  • Inform patients that LEVO-T should not be used as a primary or adjunctive therapy in a weight control program.

  • Instruct patients to notify their healthcare provider if they are taking any other medications, including prescription and over-the-counter preparations.

  • Instruct patients to notify their physician of any other medical conditions they may have,

  • particularly heart disease, diabetes, clotting disorders, and adrenal or pituitary gland problems, as the dose of medications used to control these other conditions may need to be adjusted while they are taking LEVO-T. If they have diabetes, instruct patients to monitor their blood and/or urinary glucose levels as directed by their physician and immediately report any changes to their physician. If patients are taking anticoagulants, their clotting status should be checked frequently.

  • Instruct patients to notify their physician or dentist that they are taking LEVO-T prior to any surgery.

Adverse Reactions

  • Instruct patients to notify their healthcare provider if they experience any of the following symptoms: rapid or irregular heartbeat, chest pain …

  • Inform patients that partial hair loss may occur rarely during the first few months of LEVO-T therapy, but this is usually temporary.