Differential diagnosis of low thyroid-stimulating hormone level
| Endogenous thyrotoxicosis due to single or multiple autonomously functioning or hot nodules and Graves disease |
| Thyroiditis, in which preformed hormone is released from an inflamed thyroid |
| Hypothalamic or pituitary disease (central hypothyroidism), resulting in low production of thyroid-stimulating hormone |
| Euthyroid sick syndrome (nonthyroidal illness) |
| Medication effects from glucocorticoids, exogenous thyroid hormone, lithium, amiodarone, and interferon |