Q: What is hypothyroidism and how can it be treated?

A: Hypothyroidism is a condition in which the thyroid gland does not produce enough thyroid hormone. A patient may experience symptoms such as lack of energy, weight gain, constipation, or depressed mood.

Anyone can develop hypothyroidism, but it is more prevalent in women and people over age 60. The most common cause of hypothyroidism is an autoimmune disease called Hashimoto’s disease, a disorder in which the immune system attacks the thyroid.

Other causes of hypothyroidism include surgery to remove all or part of the thyroid and radiation therapy to treat cancers of the head and neck, which can damage the thyroid. Certain medications can contribute to hypothyroidism, including lithium, which is prescribed to address specific mental disorders. Amiodarone, a medication used to treat irregular heartbeat, can also be a potential cause for hypothyroidism.

People who have a close family member with an autoimmune disease, such as celiac disease, type one diabetes, lupus, or rheumatoid arthritis, are more likely to have an autoimmune disease, as well. For this reason, doctors look at family history, particularly a parent or siblings’ medical conditions, when considering hypothyroidism as a cause for a patient’s symptoms.

It is often a patient’s primary care provider who makes the initial diagnosis through blood tests and might refer the patient to an endocrinologist who treats thyroid disorders.

The recommended treatment for hypothyroidism is thyroid hormone replacement with a medication called levothyroxine. Once someone begins taking levothyroxine, it takes about four to six weeks before blood tests will show a response to treatment. Once the patient is on a stable dose of levothyroxine, blood tests are good, and the patient feels well, a doctor may schedule follow-up office visits for every six months.

Levothyroxine is a medication that needs to be taken on an empty stomach to ensure proper absorption. Calcium, iron, and certain antacids can interfere with absorption. I recommend to my patients that they take the medication first thing in the morning with a glass of water without ingesting any other medications or food for 30 to 60 minutes. If this is not possible, I advise my patients to take levothyroxine four hours after dinner, before bedtime, to ensure that the levothyroxine is taken on an empty stomach.

Tanya Reznick is a board-certified endocrinologist with AtlantiCare Physician Group in Egg Harbor Township, N.J.