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What is Levothyroxine?

K. Willis
K. Willis

Levothyroxine is a synthetic replacement for thyroxine, a hormone normally produced in the thyroid gland. It is used to treat hypothyroidism, which is caused when the body does not produce enough of this hormone. Levothyroxine is most commonly administered in tablet form, but is also available in liquid form.

The most common symptoms of hypothyroidism include depression, dry or thickened skin, slowed speech, and fluid retention. General, diffuse aches and pains are a common symptom, as are muscle cramps, lethargy, and loss of stamina. Less common symptoms can include memory loss, infertility, irregular or heavy menstruation, and a hoarse voice.

Levothyroxine may be used to treat hypothyroidism by serving as a synthetic replacement for thyroxine.
Levothyroxine may be used to treat hypothyroidism by serving as a synthetic replacement for thyroxine.

Levothyroxine is usually taken in the morning in one single daily dose before eating, but the dosage and timing should be determined by a healthcare professional. The usual dose varies between 50 and 150 micrograms per day for adults, with a lower dose usually prescribed to begin treatment. It can take six to eight weeks for the patient to see a significant improvement in his or her condition. It is important not to take iron, calcium or aluminum containing medications at the same time as this medication.

A person with hypothyroidism has a thyroid that under-produces necessary hormones.
A person with hypothyroidism has a thyroid that under-produces necessary hormones.

Except in rare circumstances, levothyroxine will most often need to be taken for life. Occasionally, hypothyroidism will develop within six months of giving birth, but thyroxine hormone levels will usually quickly return to a normal levels. Occasionally, older children develop short-term hypothyroidism, which often requires short-term levothyroxine treatment.

Problems with the thyroid gland may cause high blood pressure.
Problems with the thyroid gland may cause high blood pressure.

Reported side effects include weight gain, nausea, headaches, and diarrhea, as well as rapid heartbeat. Allergic reactions have also been reported in some patients. If a patient suffers from any adverse effects, the medication should be stopped immediately and his or her medical professional should be consulted. Some patients have found that natural thyroxine replacement works better than levothyroxine.

Hypothyroidism can lead to irregular or heavy menstruation.
Hypothyroidism can lead to irregular or heavy menstruation.

Desiccated porcine thyroxine is basically the natural dried thyroxine of pigs. Some patients and patient advocacy groups claim that may people receive more benefits and fewer side effects from this natural hormone than synthesized levothyroxine. If a patient is planning to self-administer desiccated porcine thyroxine, the dosage must be carefully calculated to avoid consuming too much, which causes a range of health problems. As with levothyroxine, the dose of natural porcine thyroxine should be started at a low level, and increased slowly at two to three week intervals.

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    • Levothyroxine may be used to treat hypothyroidism by serving as a synthetic replacement for thyroxine.
      By: Alexander Raths
      Levothyroxine may be used to treat hypothyroidism by serving as a synthetic replacement for thyroxine.
    • A person with hypothyroidism has a thyroid that under-produces necessary hormones.
      By: reineg
      A person with hypothyroidism has a thyroid that under-produces necessary hormones.
    • Problems with the thyroid gland may cause high blood pressure.
      By: WavebreakmediaMicro
      Problems with the thyroid gland may cause high blood pressure.
    • Hypothyroidism can lead to irregular or heavy menstruation.
      By: matka_Wariatka
      Hypothyroidism can lead to irregular or heavy menstruation.
    • People who suffer from hypothyroidism often suffer from lethargy and decreased stamina.
      By: Coka
      People who suffer from hypothyroidism often suffer from lethargy and decreased stamina.
    • Problems with the thyroid gland may lead to hair loss.
      By: prudkov
      Problems with the thyroid gland may lead to hair loss.