Description and Brand Names
Drug information provided by: Merative, Micromedex®
US Brand Name
- Armour Thyroid
- Nature-Throid NT-1
- Nature-Throid NT-12
- Nature-Throid NT-2
- Nature-Throid NT-3
- Nature-Thyroid
- Westhroid
Descriptions
Thyroid is used to treat hypothyroidism, a condition where the thyroid gland does not produce enough thyroid hormone. It is also used to help decrease the size of enlarged thyroid glands (known as goiter) and to treat thyroid cancer.
Thyroid is also used in some medical tests to help diagnose problems with the thyroid gland.
This medicine is available only with your doctor's prescription.
This product is available in the following dosage forms:
Before Using
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 thyroid in children.
Geriatric
Appropriate studies performed to date have not demonstrated geriatrics-specific problems that would limit the usefulness of thyroid 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 thyroid.
Breastfeeding
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while 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 taking 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.
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.
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. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.
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:
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Adrenal insufficiency (untreated) or
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Thyrotoxicosis (overactive thyroid), untreated—Should not be used in patients with these conditions.
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Adrenal gland problems or
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Angina or
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Blood clotting problems or
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Diabetes or
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Heart or blood vessel disease (eg, coronary artery disease)—Use with caution. May make these conditions worse.
Proper Use
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.
If you are taking cholestyramine (Questran®), take it at least 4 hours before or 4 hours after you take 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.
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For oral dosage form (tablet):
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For hypothyroidism and thyroid cancer:
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Adults—At first, 30 milligrams (mg) once a day. Then, your doctor may increase your dose a little at a time up to the usual maintenance dose of 60 to 120 mg a day. A lower starting dose of 15 mg per day may be given to patients for certain conditions. Your doctor may adjust your dose as needed or tolerated.
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Children older than 12 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually more than 90 mg per day. Your doctor may adjust your dose as needed or tolerated.
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Children 6 to 12 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 60 to 90 mg per day. Your doctor may adjust your dose as needed or tolerated.
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Children 1 to 5 years of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 45 to 60 mg per day. Your doctor may adjust your dose as needed or tolerated.
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Children 6 to 12 months of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 30 to 45 mg per day. Your doctor may adjust your dose as needed or tolerated.
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Children 0 to 6 months of age—Dose is based on body weight and must be determined by your doctor. The dose is usually 15 to 30 mg 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
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
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.
Precautions
It is very important that your doctor check the progress of you or your child at regular visits. This will allow your doctor to see if the medicine is working properly and to decide if you should continue to take it. Blood tests will be needed to check for unwanted effects.
Thyroid should not be used for the treatment of obesity or for the purpose of losing weight. This medicine is ineffective for weight reduction and when taken in larger amount, it may cause more serious medical conditions.
Hypothyroidism can sometimes cause infertility in men and women. Thyroid should not be used for the treatment of infertility unless it is caused by hypothyroidism.
Call your doctor right away if you start to have chest pain, fast, irregular, pounding, or racing heartbeat or pulse, excessive sweating, heat intolerance, nervousness, or any other unusual medical condition.
For patients with diabetes: It is very important that you keep track of your blood or urine sugar levels as instructed by your doctor. Check with your doctor immediately if you notice any changes in your sugar levels.
A temporary loss of hair may occur during the first few months of thyroid therapy. Ask your doctor about this if you have any concerns.
Do not suddenly stop taking this medicine without first checking with your doctor. Your doctor may want you or your child to gradually reduce the amount you are using before stopping completely.
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.
Side Effects
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Get emergency help immediately if any of the following symptoms of overdose occur:
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Changes in appetite
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changes in menstrual periods
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chest pain
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diarrhea
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fast or irregular heartbeat
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fever
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hand tremors
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headache
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irritability
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leg cramps
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nervousness
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sensitivity to heat
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sweating
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trouble breathing
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trouble sleeping
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vomiting
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weight loss
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Portions of this document last updated: July 01, 2024
Original article: https://www.mayoclinic.org/zh-hans/drugs-supplements/thyroid-oral-route/before-using/drg-20069086