By Dr Ananya Mandal, MD
Hypothyroidism is a disease of the thyroid gland that affects the amount of thyroxine produced by the gland. Management of this condition involves using hormone replacement therapy to replace this thyroxine.
A synthetic form of thyroxine is available as a medication called levothyroxine, which can be taken as an oral tablet on a daily basis. At first, patients are given regular blood tests to check whether their dose of the drug is correct. The patient may be started on a low dose initially and then gradually work up towards a greater dose, depending on their response to the medication. For example, some patients begin to feel an improvement in symptoms almost immediately, whereas others notice no effects for several months when the correct dose is established.
Once the correct dose is reached, patients have blood tests on an annual basis to monitor their hormone levels. In some cases, initial tests may suggest that a patient is at risk of hypothyroidism and they do not yet have any symptoms. These patients usually have a blood test every few months to monitor their hormone levels so that levothyroxine can be prescribed if they do develop hypothyroidism.
Patients who take levothyroxine should take their tablet at the same time each day on an empty stomach because absorption of the medication is affected by food. Patients usually need to take this medication for the rest of their lives, but can usually lead a full and active life.
As this therapy simply replaces depleted levels of thyroxine, it is not usually associated with any side effects. However, if a patient takes too much of the drug, they may experience symptoms such as headache, sweating, diarrhea, vomiting and chest pain. Patients should seek medical attention if any of these symptoms develop.
Reviewed by Sally Robertson, BSc
Last Updated: Nov 5, 2014