Facts about Synthroid side effects

Synthroid side effects :
a look at Purpose, Use and Impact

Synthroid (Levothyroxine), a thyroid hormone, is used to treat hypothyroidism, a condition where the thyroid gland does not produce enough thyroid hormone. Without this hormone, the body cannot function properly, resulting in poor growth, slow speech, lack of energy, weight gain, hair loss, dry thick skin, and increased sensitivity to cold. When taken correctly, levothyroxine reverses these symptoms. Levothyroxine also is used to treat congenital hypothyroidism (cretinism) and goiter (enlarged thyroid gland).

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Special Warning about Synthroid side effects

According to The American Society of Health-System Pharmacists (ASHP),"Thyroid hormone should not be used to treat obesity in patients with normal thyroid function. Levothyroxine is ineffective for weight reduction in normal thyroid patients and may cause serious or life-threatening toxicity, especially when taken with amphetamines. Talk to your doctor about the potential risks associated with this medication."

Synthroid side effects and interactions

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, Synthroid side effects 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.

Observed Synthroid side effects

Along with its needed effects, there may be unwanted Synthroid side 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 Commonly Observed

Headache (severe) in children; skin rash or hives.

Synthroid side effects from 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, this medicine usually takes several weeks to have a noticeable effect on your condition. Until it begins to work, you may experience no change in your symptoms. Check with your doctor if the following symptoms continue: Clumsiness; coldness; constipation; dry, puffy skin; listlessness; muscle aches; sleepiness; tiredness; weakness; weight gain.

Other Synthroid 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 Synthroid side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.

Sources : The American Society of Health-System Pharmacists (ASHP) and the United States Pharmacopeia (USP)

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More information here.


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