Description
Thyroid medicines belong to the general group of medicines called hormones. They are used
when the thyroid gland does not produce enough hormone. They are also used to help
decrease the size of enlarged thyroid glands (known as goiter) and to treat thyroid
cancer.
Proper Use of This Medicine
Use this medicine only as directed by your doctor. Do not use more or less of it,
and do not use it more often than your doctor ordered. Your doctor has prescribed the
exact amount your body needs and if you take different amounts, you may experience
symptoms of an overactive or underactive thyroid. Take it at the same time each day to
make sure it always has the same effect.
If your condition is due to a lack of thyroid hormone, you may have to take this medicine for the rest of your life. It is very important that you do not stop taking this medicine without first checking with your doctor.
Dosing - The dose of these medicines 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 these medicines. If your dose is different, do not change it unless your doctor tells you to do so.
The number of tablets that you take depends on the strength of the medicine. The amount of thyroid hormone that you need to take every day depends on the results of your thyroid tests. However, treatment is usually started with lower doses that are increased a little at a time until you are taking the full amount. This helps prevent side effects.
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. If you miss 2 or more doses in a row or if you have any questions about this, check with your doctor.
Storage - To store this medicine:
Before Using This Medicine
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 thyroid
hormones, the following should be considered:
Allergies - Tell your doctor if you have ever had any unusual or allergic reaction to thyroid hormones. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.
Pregnancy - Use of proper amounts of thyroid hormone during pregnancy has not been shown to cause birth defects or other problems. However, your doctor may want you to change your dose while you are pregnant. This will make regular visits to your doctor important.
Breast-feeding - Use of proper amounts of thyroid hormones by mothers has not been shown to cause problems in nursing babies.
Children - Thyroid hormones have been tested in children and have not been shown to cause different side effects or problems in children than they do in adults.
Older adults - This medicine has been tested and has not been shown to cause different side effects or problems in older people than it does in younger adults. However, a different dose may be needed in the elderly. Therefore, it is important to take the medicine only as directed by the doctor.
Other 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 necessary. When you are taking thyroid hormones, it is especially important that your health care professional know if you are taking any of the following:
Other medical problems - The presence of other medical problems may affect the use of thyroid hormones. Make sure you tell your doctor if you have any other medical problems especially:
Precautions While Using This Medicine
It is very important that your doctor check your progress at regular visits, to
make sure that this medicine is working properly.
If you have certain kinds of heart disease, this medicine may cause chest pain or shortness of breath when you exert yourself. If these occur, do not overdo exercise or physical work. If you have any questions about this, check with your doctor.
Before having any kind of surgery (including dental surgery) or emergency treatment, tell the medical doctor or dentist in charge that you are taking this medicine.
Do not take any other medicine unless prescribed by your doctor. Some medicines may increase or decrease the effects of thyroid on your body and cause problems in controlling your condition. Also, thyroid hormones may change the effects of other medicines.
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.
Check with your doctor as soon as possible if any of the following side effects occur since they may indicate an overdose or an allergic reaction:
Less common or rare
Headache (severe) in children, skin rash or hives
Signs and symptoms of overdose
Chest pain, confusion, fast or irregular heartbeat, mood swings , muscle weakness, psychosis , restlessness (extreme), yellow eyes or skin, shortness of breath
For patients taking this medicine for underactive thyroid:
Clumsiness, coldness, constipation, dry, puffy skin, listlessness, muscle aches, sleepiness, tiredness, weakness, weight gain
Other effects may occur if the dose of the medicine is not exactly right. These side effects will go away when the dose is corrected. Check with your doctor if any of the following symptoms occur:
Changes in appetite, changes in menstrual periods, diarrhea, fever , hand tremors, headache , increased sensitivity to heat, irritability, leg cramps, nervousness, sweating, trouble in sleeping, vomiting, weight loss
Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.