Levothyroxine Sodium, also known as L-thyroxine, synthetic T4 or simply 3,5,3',5'-tetraiodo-L-thyronine, is a synthetic form of thyroxine (thyroid hormone). As the hormone is chemically in the L-form (instead of D, see chirality), it is metabolised much slower than physiological thyroid hormone, which has a shorter half-life.

The EU has recently standardised the use of the name "levothyroxine" for the drug. Common brand names include "Thyrax", "Euthyrox", "Levaxin" and "Eltroxin" in Europe, and "Levoxyl" and "Synthroid" in the US.

This medicine is usually given to patients with thyroid problems. These many problems can affect the patient's (if he/she is a child/teenager) growth and/or weight.

It is recommended that levothyroxine is taken an hour before meals to maximise its absorption.

External links

• Detailed Euthyrox (Levothroid/Levothyroxine) Consumer Information: Uses, Precautions, Side Effects

Hormonal agents

Levothyroxin | Levothyroxine