What is levothyroxine?

Levothyroxine is a synthetic hormone given to patients who have hypothyroidism or low levels of T4, according to Drugs.com. Levothyroxine is identical to the hormone produced by the thyroid gland, and it is easily tolerated by the body.

Levothyroxine should be taken at the same time every day 30 minutes to one hour before eating, according to WebMD. There are several different brand names of levothyroxine, and an individual may need a trial of different brands to find the one that works best. It may also take trials of several dosage strengths and lab tests before finding the right levothyroxine level to alleviate a patient's symptoms.