Updated December 29, 2014. Question: Levothyroxine: Is there a difference between brand name and generic versions? From a reader: I recently was switched from Synthroid to generic levothyroxine for my thyroid condition.
Updated November 25, 2014. Question: Levothyroxine / L-Thyroxine Answer: Pronunciation: lee-voe-thye-ROCKS -een, ell-thye-ROCKS -een Brand Names. Brand names in the U.S: Synthroid, Levothroid, Levoxyl, Unithroid Brand names in Canada: Synthroid, Eltroxin, and PMS-Levothyroxine Brand names outside U.S.: Euthyrox, Thyroxine, Berlthyrox, Droxine, Eferox, Elthyrone, Eltroxin, Eutirox, Letrox, Levaxin, Levotirox, Levothyrox, Levotiroxina, Oroxine, T4KP, Thevier, Throxinique, Thyradin.
Response by: Carmen M Hadley, RPh, CSPI Former Clinical Instructor College of Pharmacy. The Ohio State University.
Thyroxine preparations (including both L and D isomers) are currently not produced in the Unites States. Dosing of levothyroxine is typically based on thyroid-stimulating hormone levels in the blood. Your doctor can help find a dose that will provide you with sufficient amounts of T4 (thyroxine).
On a chemical level Levothyroxine is an isomer of thyroxine which essentially means that levothyroxine molecules are chemically the same as thyroxine molecules but take on a different shape than thyroxine; both have the same effect in the body on metabolic function.
Hypothyroidism can be treated with medications that are either animal-derived or synthetically-created thyroid hormones. Such medications can provide T3, T4, or both T3 and T4 in one tablet. Levothyroxine is a generic medication used to treat hypothyroidism that provides your body with synthetic T4 (thyroxine) which can be converted inside your body to T3.
Your doctor may change your dose of thyroid hormone, but the brand of your thyroid hormone medication should always stay the same. Related Articles: Should You Be Concerned About Taking Generic Thyroid Drugs?
There are four well-tested, brand name preparations of levothyroxine available in the United States for the treatment of people with hypothyroidism (low thyroid) Levothroid, Levoxyl, Synthroid, and Unithroid. Although there are differences in how these products are manufactured, such as the use of coloring dyes and fillers, each of these brand-name medications is reliable.
Practically speaking, this means your doctor may need to perform more frequent blood tests and perhaps change the dose of your medication. Although your symptoms of feeling crummy may be a coincidence or due to some other health problem, it is possible that your body was reacting to a difference between Synthroid and generic levothyroxine.
Its important that you discuss these changes with your physician. According to the American Association of Clinical Endocrinologists, you should use the same brand of thyroid medication throughout your treatment. Thyroid disease often requires lifelong therapy and is best managed with consistent and precise treatment with the same brand of thyroid hormone.
Description Levothyroxine is the generic name for the synthetic form of thyroxine, a thyroid hormone replacement drug. This drug contains the synthetic form of one thyroid hormone, T4. Levothyroxine is the most commonly prescribed thyroid hormone replacement drug.
Thyroxine Vs Levothyroxine Question: Dear Pharmacist, What is the difference between Levothyroxine and Thyroxine? Can I use it interchangeably if one is not available? Is it equivalent in dosage? Answer: Your body produces two types of thyroid hormones, triiodothyronine (abbreviated T3 and thyroxine (abbreviated T4).
The thyroid gland produces more T4 than T3, but the T3 is more biologically active. T4 can be converted to T3 in order to provide the body with the more active thyroid hormone.