Medically reviewed by Drugs.com. Last updated on Mar 3, 2022.
Commonly used brand name(s)
In the U.S.
- Synthroid
Available Dosage Forms:
- Powder for Solution
Therapeutic Class: Thyroid Supplement
Uses for levothyroxine
Levothyroxine injection is used to treat myxedema coma (severe hypothyroidism), a condition where the thyroid gland does not produce enough thyroid hormone. The powder form of levothyroxine injection can be used as a substitute for the oral dose when a rapid effect is needed and when the oral route is not allowed.
Levothyroxine is to be given only by or under the supervision of your doctor.
Before using levothyroxine
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For levothyroxine, the following should be considered:
Allergies
Tell your doctor if you have ever had any unusual or allergic reaction to levothyroxine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Pediatric
Appropriate studies performed to date have not demonstrated pediatrics-specific problems that would limit the usefulness of levothyroxine injection in the pediatric population.
Geriatric
Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of levothyroxine injection in the elderly. However, elderly patients are more likely to have age-related heart and blood vessel problems, which may require caution in patients receiving levothyroxine injection.
Breastfeeding
Studies in women suggest that this medication poses minimal risk to the infant when used during breastfeeding.
Interactions with medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessa...
