TSH (Thyroid-Stimulating Hormone)

TSH is a hormone produced by the pituitary gland in the brain. TSH causes the thyroid gland (located in the neck) to produce thyroid (T4 and T3).

Having a high TSH level means you are "hypothyroid." Symptoms can include fatigue, constipation, and weight gain. When there are low levels of thyroid hormone (hypothyroidism), the TSH becomes elevated as the body tries to increase thyroid production.

Having a low TSH level means you are "hyperthyroid." Symptoms can include weight loss and nervousness. When there are high levels of thyroid hormone (hyperthyroidism), the TSH falls as the body tries to slow thyroid production.

• Interferon treatment can cause thyroid changes, so you could see a TSH level rise or fall when you are receiving interferon.
• Occasionally, patients on interferon need to take medication to correct their TSH levels.
• Hepatitis C itself also can cause thyroid changes, even without the interferon treatment.
• In general, thyroid problems are common and occur without hepatitis C.