Before Using

Drug information provided by: Merative, Micromedex®

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 this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine 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.

Drug Interactions

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 necessary. When you are receiving this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Digitalis
  • Furosemide
  • Iopromide
  • Ketamine
  • Midodrine
  • Rifampin

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Afatinib
  • Alectinib
  • Baricitinib
  • Capmatinib
  • Chlorotrianisene
  • Cholestyramine
  • Chromium
  • Colesevelam
  • Conjugated Estrogens
  • Conjugated Estrogens Synthetic A
  • Conjugated Estrogens Synthetic B
  • Dexlansoprazole
  • Dienestrol
  • Diethylstilbestrol
  • Esomeprazole
  • Esterified Estrogens
  • Estradiol
  • Estramustine
  • Estriol
  • Estropipate
  • Ethinyl Estradiol
  • Fosphenytoin
  • Fostamatinib
  • Gefitinib
  • Imatinib
  • Kelp
  • Lansoprazole
  • Lanthanum Carbonate
  • Lopinavir
  • Mestranol
  • Nintedanib
  • Omeprazole
  • Pantoprazole
  • Phenytoin
  • Polyestradiol Phosphate
  • Promestriene
  • Quinestrol
  • Rabeprazole
  • Ritonavir
  • Sevelamer
  • Simvastatin
  • Tibolone
  • Tucatinib

Other Interactions

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following is usually not recommended, but may be unavoidable in some cases. If used together, your doctor may change the dose or how often you use this medicine, or give you special instructions about the use of food, alcohol, or tobacco.

  • Dietary Fiber
  • Grapefruit Juice
  • Soybean
  • Walnut

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

  • Adrenal insufficiency or Addison's disease (adrenal gland problem), uncorrected or
  • Thyrotoxicosis (overactive thyroid)—Should not be used in patients with these conditions.
  • Clotting disorder or
  • Diabetes or
  • Heart disease (history of) or
  • Underactive pituitary gland—Use with caution. May side effects to become worse.