Proper Use

Drug information provided by: Merative, Micromedex®

This medicine will need to be taken for the rest of your life or your child's life. Do not stop taking this medicine or change your dose without first checking with your doctor. You may have to take this medicine for 4 to 8 weeks before your symptoms start to get better.

Take this medicine in the morning on an empty stomach, at least 30 to 60 minutes before eating breakfast.

Swallow the capsule whole. Do not cut, chew, or crush it.

If your child is unable to swallow the tablet, you may crush and mix it in 1 to 2 teaspoons (5 to 10 milliliters) of water. Give the mixture right away using a spoon or dropper. Do not mix the tablet with any other liquid except water. Do not store the mixture for future use.

If you are using the oral liquid:

  • This medicine may be mixed with water or be given directly into the mouth.
  • If mixed with water, squeeze the contents of 1 single unit-dose ampule into a glass or cup containing water. Stir and drink it immediately. Add some water to the glass or cup and drink the water. This will help get all of the medicine out of the glass or cup. Do not mix this medicine with any other liquid except water. Do not store the mixture for later use.
  • If taken without water, squeeze the medicine directly into the mouth or into a spoon and swallow it immediately.

If you are using kayexalate, lanthanum, orlistat, sevelamer, sucralfate, antacids (eg, aluminum or magnesium hydroxide, simethicone, Maalox®, Mylanta®, Tums®), medicine to lower cholesterol (eg, cholestyramine, colesevelam, colestipol, Prevalite®,Welchol®, Colestid®), stomach medicine (eg, lansoprazole, omeprazole, pantoprazole, Aciphex®, Dexilant®, Nexium®, Prevacid®, Prilosec®), or any medicine that contains calcium or iron, take them at least 4 hours before or 4 hours after you take levothyroxine.

Cotton seed meal, dietary fiber, soybean flour (infant formula), or walnuts may decrease the absorption of this medicine from your body. You may have to take this medicine at a different time of day from when you eat these foods. Talk with your doctor more about this if you have concerns.

Do not eat grapefruit or drink grapefruit juice while you are using this medicine.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage form (capsules):
    • For hypothyroidism:
      • Adults and children older than 12 years of age (growth and puberty complete)—Dose is based on body weight and must be determined by your doctor. The dose is usually 1.7 microgram (mcg) per kilogram (kg) of body weight per day but may be less in older adults.
      • Children older than 12 years of age (growth and puberty incomplete)—Dose is based on body weight and must be determined by your doctor. The dose is usually 2 to 3 mcg per kg of body weight per day.
      • Children 6 to 12 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 4 to 5 mcg per kg of body weight per day.
      • Children younger than 6 years of age—Use is not recommended as your child might not be able to swallow the capsules.
    • For thyroid cancer:
      • Adults—Dose is based on body weight and must be determined by your doctor. The dose is usually more than 2 microgram (mcg) per kilogram (kg) of body weight per day.
      • Children—Use and dose must be determined by your doctor.
  • For oral dosage form (solution):
    • For hypothyroidism:
      • Adults and children older than 12 years of age (growth and puberty complete)—Dose is based on body weight and must be determined by your doctor. The starting dose is usually 1.7 microgram (mcg) per kilogram (kg) of body weight per day. Your doctor may adjust your dose as needed.
      • Children older than 12 years of age (growth and puberty incomplete)—Dose is based on body weight and must be determined by your doctor. The dose is usually 2 to 3 mcg per kg of body weight per day.
      • Children 6 to 12 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 4 to 5 mcg per kg of body weight per day.
      • Children 1 to 5 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 5 to 6 mcg per kg of body weight per day.
      • Children 6 to 12 months of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 6 to 8 mcg per kg of body weight per day.
      • Children 3 to 6 months of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 8 to 10 mcg per kg of body weight per day.
      • Children 0 to 3 months of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 10 to 15 mcg per kg of body weight per day.
    • For thyroid cancer:
      • Adults—Dose is based on body weight and must be determined by your doctor. The dose is usually more than 2 microgram (mcg) per kilogram (kg) of body weight per day.
      • Children—Use and dose must be determined by your doctor.
  • For oral dosage form (tablet):
    • For hypothyroidism:
      • Adults and children older than 12 years of age (growth and puberty complete)—Dose is based on body weight and must be determined by your doctor. The dose is usually 1.6 microgram (mcg) per kilogram (kg) of body weight per day but may be less in older adults. Your doctor may adjust your dose as needed or tolerated.
      • Children older than 12 years of age (growth and puberty incomplete)—Dose is based on body weight and must be determined by your doctor. The dose is usually 2 to 3 mcg per kg of body weight per day. Your doctor may adjust your dose as needed or tolerated.
      • Children 6 to 12 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 4 to 5 mcg per kg of body weight per day. Your doctor may adjust your dose as needed or tolerated.
      • Children 1 to 5 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 5 to 6 mcg per kg of body weight per day. Your doctor may adjust your dose as needed or tolerated.
      • Children 6 to 12 months of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 6 to 8 mcg per kg of body weight per day. Your doctor may adjust your dose as needed or tolerated.
      • Children 3 to 6 months of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 8 to 10 mcg per kg of body weight per day. Your doctor may adjust your dose as needed or tolerated.
      • Children 0 to 3 months of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 10 to 15 mcg per kg of body weight per day. Your doctor may adjust your dose as needed or tolerated.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Use the oral liquid within 15 days after opening the pouch. Keep the ampules in the pouch until you are ready to use them.

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Portions of this document last updated: July 01, 2023