levothyroxine (generic name)

Evotrox (brand name)

This medicine can improve symptoms of thyroid deficiency such as slow speech, lack of energy, weight gain, hair loss, dry skin, and feeling cold
(lee voe thye ROX een)
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What is this medicine?

LEVOTHYROXINE (lee voe thye ROX een) is a thyroid hormone. This medicine can improve symptoms of thyroid deficiency such as slow speech, lack of energy, weight gain, hair loss, dry skin, and feeling cold. It also helps to treat goiter (an enlarged thyroid gland).

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:
  • angina
  • diabetes
  • dieting or on a weight loss program
  • fertility problems
  • heart disease
  • high levels of thyroid hormone
  • pituitary gland problem
  • previous heart attack
  • an unusual or allergic reaction to levothyroxine, thyroid hormones, other medicines, foods, dyes, or preservatives
  • pregnant or trying to get pregnant
  • breast-feeding

How should I use this medicine?

This medicine is for injection into a muscle or into a vein. It is given by a health care professional in a hospital or clinic setting.

Contact your pediatrician regarding the use of this medicine in children. While this drug may be prescribed for children and infants as young as a few days of age for selected conditions, precautions do apply.

What if I miss a dose?

This does not apply.

What may interact with this medicine?

  • amiodarone
  • carbamazepine
  • digoxin
  • female hormones, including contraceptive or birth control pills
  • ketamine
  • medicines for colds and breathing difficulties
  • medicines for diabetes
  • medicines for mental depression
  • medicines or herbals used to decrease weight or appetite
  • phenobarbital or other barbiturate medications
  • phenytoin
  • prednisone or other corticosteroids
  • rifabutin
  • rifampin
  • soy isoflavones
  • theophylline
  • warfarin

What should I watch for while using this medicine?

You will need regular exams and occasional blood tests to check the response to treatment. If you are receiving this medicine for an underactive thyroid, it may be several weeks before you notice an improvement. Check with your doctor or health care professional if your symptoms do not improve.

It may be necessary for you to take this medicine for the rest of your life. Do not stop using this medicine unless your doctor or health care professional advises you to.

This medicine can affect blood sugar levels. If you have diabetes, check your blood sugar as directed.

You may lose some of your hair when you first start treatment. With time, this usually corrects itself.

If you are going to have surgery, tell your doctor or health care professional that you are taking this medicine.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:
  • difficulty breathing, wheezing, or shortness of breath
  • chest pain
  • excessive sweating or intolerance to heat
  • fast or irregular heartbeat
  • nervousness
  • skin rash or hives
  • swelling of ankles, feet, or legs
  • tremors

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • changes in appetite
  • changes in menstrual periods
  • diarrhea
  • hair loss
  • headache
  • trouble sleeping
  • weight loss

Where should I keep my medicine?

This does not apply. This medicine will be given to you in a hospital or health clinic setting. You will not store this medicine at home.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Last Updated: January 10, 2013
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