Several types of steroid hormones are produced in the adrenal glands, and in the gonads (ovaries or testicles). The most common class of steroid hormone used to treat a broad variety of diseases is known as the glucocorticoids. Representative glucocorticoids include cortisone, prednisone, hydrocortisone, dexamethasone, and methylprednsone.
These agents are frequently used to treat inflammatory disease such as arthritis, collagen vascular diseases, lung inflammation and asthma, certain types of liver inflammation, some skin diseases and granulomatous diseases.
Glucocorticoids may also affect thyroid function. In high doses, glucocorticoids reduce the conversion of active thyroxine (T4) to the more active triiodothyronine (T3). Hence, in patients with severe hyperthyroidism, glucocorticoids may be used to reduce the levels of circulating thyroid hormones. Glucocorticoids may also decrease pituitary production of TSH, if given in sufficiently high doses.
As glucocorticoids tend to exert anti-inflammatory effects on various tissues, patients with Hashimoto's thyroiditis will also tend to notice improvement of thyroid function and reduction in thyroid size if they are treated with glucocorticoids. Similarly, patients with Grave's eye disease that have thickened eye muscles and problems with vision due to inflammation and thickening of the eye muscles may also benefit from treatment with glucocorticoids.
It is important to remember that glucocorticoids are extremely potent medications that can be associated with the rapid development of many side effects, such as: sleep disturbances, changes in mood, fluid retention, acne and thinning of the skin, increased appetite and weight gain, high blood pressure, diabetes, enhanced susceptibility to life-threatening infections, osteonecrosis of joints and osteoporosis.
Accordingly, glucocorticoids should only be used in extreme cases of thyroid dysfunction, and for as limited a treatment period as possible.