Organization Of Guidelines: Section I. Levothyroxine Therapy
| Number | Question | Page |
|---|---|---|
| Levothyroxine Therapy and Endpoints During Therapy | ||
| 1a | Is levothyroxine monotherapy considered to be the standard of care for hypothyroidism? | 1676 |
| 1b | What are the clinical and biochemical goals for levothyroxine replacement in primary hypothyroidism? | 1677 |
| 1c | Are clinical parameters such as cold sensitivity and dry skin useful by themselves for assessing adequacy of levothyroxine replacement in primary hypothyroidism? | 1678 |
| 1d | Are tissue markers of thyroid hormone action helpful in determining the adequacy of levothyroxine replacement in primary hypothyroidism? | 1679 |
| Choice of Levothyroxine Product | ||
| 2a | Is there a clinical rationale for prescribing brand-name levothyroxine preparations in preference to generic levothyroxine? | 1679 |
| 2b | Are there situations in which therapy with levothyroxine dissolved in glycerin and supplied in gelatin capsules may have advantages over standard levothyroxine? | 1681 |
| Levothyroxine Absorption and Metabolism | ||
| 3a | How should levothyroxine administration be timed with respect to meals and beverages in order to maintain maximum, consistent absorption? | 1681 |
| 3b | Are there medications and supplements that should not be co-administered with levothyroxine in order to avoid impaired absorption? | 1682 |
| 3c | Are there gastrointestinal conditions that should be considered when a patient's levothyroxine dose is much higher than expected? | 1683 |
| 3d | Are different levothyroxine products associated with different absorption, such that a switch to a different brand name or generic is associated with a significantly different serum thyrotropin? | 1684 |
| 3e | What medications may alter a patient's levothyroxine requirement by affecting either metabolism or binding to transport proteins? | 1685 |
| Levothyroxine Dosage | ||
| 4a | What factors determine the levothyroxine dose required by a hypothyroid patient for reaching the appropriate serum thyrotropin goal? | 1686 |
| 4b | What is the best approach to initiating and adjusting levothyroxine therapy? | 1687 |
| 4c | What are the potential deleterious effects of excessive levothyroxine? | 1688 |
| 4d | What are the potential deleterious effects of inadequate levothyroxine? | 1688 |
| Levothyroxine and Other Nonhypothyroid Medical Conditions | ||
| 5a | What is the appropriate management of perceived allergy to the constituents of levothyroxine or intolerance to levothyroxine? | 1689 |
| 5b | How do co-existent medical conditions (e.g., atherosclerotic coronary artery disease) affect the management of levothyroxine replacement therapy? | 1689 |
| 5c | How do coexistent psychosocial, behavioral, and mental health conditions (such as addiction, somatization disorder, and depression) affect the management of levothyroxine therapy? | 1689 |
| Levothyroxine Therapy in Specific Subpopulations | ||
| 6a | How should levothyroxine therapy be managed in the elderly with hypothyroidism? | 1690 |
| 6b | How should levothyroxine therapy be managed in pregnant women with hypothyroidism? | 1691 |
| 6c | How should levothyroxine therapy be managed in infants and children with overt hypothyroidism? | 1691 |
| 6d | How should levothyroxine therapy be managed in children with subclinical hypothyroidism? | 1691 |
| 6e | How should levothyroxine therapy be managed in individuals who have elevated thyrotropin values due to nonadherence? | 1693 |
| Levothyroxine and Serum Triiodothyronine Concentrations | ||
| 7a | Are variations in serum triiodothyronine concentrations within the reference range of physiologic or clinical significance? In addition, are mildly low serum triiodothyronine concentrations of clinical significance? | 1694 |
| 7b | Does levothyroxine therapy that returns the serum thyrotropin levels of hypothyroid patients to the reference range also result in normalization of their serum triiodothyronine levels? | 1695 |
| 7c | Is there evidence of discordance between the thyroid hormone status of different tissues and the serum thyrotropin concentration? | 1696 |
| 7d | Should levothyroxine therapy for hypothyroidism, particularly in specific subgroups such as those with obesity, depression, dyslipidemia, or who are athyreotic, be targeted to achieve high-normal serum triiodothyronine levels or low-normal serum thyrotropin levels? | 1697 |
| Levothyroxine Therapy in Secondary Hypothyroidism | ||
| 8a | What biochemical goals should be employed for levothyroxine replacement in patients with secondary hypothyroidism? | 1698 |
| 8b | Are clinical parameters useful for assessing adequacy of levothyroxine replacement in patients with secondary hypothyroidism? | 1699 |
| 8c | Are tissue markers of thyroid hormone action helpful for management of levothyroxine replacement in patients with secondary hypothyroidism? | 1699 |
| Patient Satisfaction with Levothyroxine Therapy | ||
| 9a | What tools may be useful in the clinical or research setting, to measure the impact of levothyroxine replacement for primary hypothyroidism on patients' physical or psychological well-being, treatment satisfaction, or treatment preferences? | 1700 |
| 9b | What approach should be taken in patients treated for hypothyroidism who have normal serum thyrotropin values but still have unresolved symptoms? | 1700 |
| Use of Levothyroxine in Euthyroid Individuals | ||
| 10a | Is there a role for the use of levothyroxine to treat biochemically euthyroid patients with symptoms that overlap with those of hypothyroidism? | 1701 |
| 10b | Is there a role for the use of levothyroxine to treat euthyroid patients with depression? | 1702 |
| 10c | Is there a role for the use of levothyroxine to treat euthyroid patients with obesity? | 1702 |
| 10d | Is there a role for the use of levothyroxine to treat euthyroid patients with urticaria? | 1703 |
| 10e | What is the recommended approach to treating factitious thyrotoxicosis? | 1703 |
| Clinical Ethics Considerations in Levothyroxine Treatment | ||
| 11 | What are the ethical obligations of clinicians in treating hypothyroidism? | 1703 |
| SECTION II. THERAPIES OTHER THAN LEVOTHYROXINE ALONE | ||
| Thyroid Extracts | ||
| 12 | In adults requiring thyroid hormone replacement treatment for primary hypothyroidism, is treatment with thyroid extracts superior to treatment with levothyroxine alone? | 1704 |
| Synthetic Combination Therapy and the Rationale for Its Use | ||
| 13a | Do genetic variants in thyroid hormone pathway genes (deiodinases or thyroid hormone transporters) affect the serum or tissue levels of thyroid hormones in healthy euthyroid individuals or hypothyroid patients taking replacement therapy? | 1706 |
| 13b | In adults requiring thyroid hormone replacement treatment for primary hypothyroidism, is combination treatment including levothyroxine and liothyronine superior to the use of levothyroxine alone? | 1707 |
| 13c | In adults requiring thyroid hormone replacement treatment for primary hypothyroidism who feel unwell while taking levothyroxine, is combination treatment including levothyroxine and liothyronine superior to the use of levothyroxine alone? | 1707 |
| 13d | Should genetic characterization according to type 2 deiodinase gene polymorphism status be used to guide the use of combination synthetic levothyroxine and liothyronine therapy in hypothyroidism, in order to optimize biochemical and clinical outcomes? | 1712 |
| Liothyronine Monotherapy for Hypothyroidism | ||
| 14 | Are there data regarding therapy with triiodothyronine alone, either as standard liothyronine or as sustained release triiodothyronine, that support the use of triiodothyronine therapy alone for the treatment of hypothyroidism? | 1713 |
| Liothyronine Monotherapy in Euthyroid Patients | ||
| 15a | Is there a role for the use of liothyronine to treat biochemically euthyroid patients with depression? | 1714 |
| 15b | Is there a role for the use of liothyronine to treat biochemically euthyroid patients with obesity? | 1715 |
| Compounded Thyroid Hormones | ||
| 16 | What is the recommendation regarding therapy with compounded thyroid hormones (either levothyroxine or liothyronine) for treatment of hypothyroidism based on current evidence? | 1715 |
| Nutraceuticals | ||
| 17 | Is there a role for the use of dietary supplementation, nutraceuticals, and over-the-counter products in either hypothyroid or euthyroid individuals? | 1716 |
| Ethical Considerations in Hypothyroidism Research | ||
| 18 | What are the research ethics issues involved in evaluating or designing clinical trials for the treatment of hypothyroidism? | 1718 |
| Wilson's Syndrome | ||
| 19 | Is there evidence for the existence of “Wilson's temperature syndrome” and a rationale for use of escalating doses of triiodothyronine? | 1719 |
| SECTION III. HOSPITALIZED PATIENTS | ||
| Number | Question | Page |
| Levothyroxine in Hospitalized Patients | ||
| 20a | In hospitalized but not critically ill patients with known pre-existing hypothyroidism, should levothyroxine therapy be re-evaluated based on an elevated serum thyrotropin measurement? | 1720 |
| 20b | In hospitalized but not critically ill patients in whom levothyroxine replacement is instituted or increased, should the therapeutic goal be normalization of serum thyrotropin? | 1720 |
| 20c | In hospitalized but not critically ill patients treated with levothyroxine replacement what formulation and route of administration are recommended? | 1720 |
| 20d | In hospitalized but not critically ill patients about to be treated with levothyroxine should the possibility of adrenal insufficiency be excluded? | 1720 |
| Myxedema Coma | ||
| 21a | In patients with myxedema coma being treated with levothyroxine, what route of administration should be used? | 1721 |
| 21b | In patients with myxedema coma being treated with levothyroxine, should empiric glucocorticoid coverage be provided? | 1721 |
| 21c | In patients with myxedema coma being treated with levothyroxine, should liothyronine therapy also be initiated? | 1721 |
| 21d | In patients with myxedema coma being treated with levothyroxine, what therapeutic endpoints should be targeted? | 1721 |
| Low Triiodothyronine Concentrations in Hospitalized Patients | ||
| 22a | In hospitalized adult patients exhibiting the “nonthyroidal illness syndrome,” should thyroid hormone replacement be instituted with levothyroxine? | 1722 |
| 22b | In hospitalized adult patients exhibiting the “nonthyroidal illness syndrome,” should thyroid hormone replacement be instituted with liothyronine? | 1722 |
| 22c | In hospitalized adult patients with cardiac dysfunction, such as advanced heart failure, and low serum triiodothyronine concentrations, should thyroid hormone replacement be instituted with liothyronine? | 1724 |
| SECTION IV. USE OF THYROID HORMONE ANALOGS | ||
| Thyroid Hormone Analogs and Euthyroid Patients | ||
| 23 | Should thyroid hormone analog therapy be used in euthyroid individuals with non–hypothyroid-related medical conditions (such as dyslipidemia) based on current evidence? | 1725 |
| Thyroid Hormone Analogs and Thyroid Hormone Resistance | ||
| 24a | What are the clinical and biochemical goals for treatment of patients who have genetic syndromes of resistance to thyroid hormone? | 1726 |
| 24b | What is the role of thyroid hormone analogs in treating patients who have genetic syndromes of resistance to thyroid hormone? | 1726 |