Levothyroxine is an essential medications that is a synthetic form of thyroxine – a form of thyroid hormone.

Under normal circumstances, this hormone is produced in the Thyroid gland and secreted by the follicular cells.

Thyroxine was initially isolated in pure form in 1914 at the Mayo Clinic. This was done by Edward Calvin Kendall from thyroid glands from hogs.

The hormone was synthesized in 1927. It can be given Orally (most often) or Intravenously.


1.)  Eutirox
2.)  Levoxyl
3.)  Synthroid
4.)  Eltroxin
5.)  Levaxin


1.)  Hormone replacement for goiter.

2.)  Hypothyroidism

3.)  Occasionally used to prevent the recurrence of Thyroid Cancer.

4.)  And other thyroid problems

Hypothyroidism in a nut shell

Hypothyroidism is a condition where the thyroid gland does not produce enough thyroid hormone.

Without this hormone, the body cannot function properly.

Results of low thyroid hormone results in:

–  Poor growth
–  Slow speech
–  Lack of energy
–  Weight gain
–  Hair loss
–  Dry and thick skin
–  Increased sensitivity to cold.

Adverse Effects of this Medication

–  Nausea
–  Insomnia
–  Swelling
–  Weight loss
–  Increased appetite
–  Excessive high amounts of this medication can cause side effects that mimic Hyperthyroidism.

Overdose Side Effects

–  Abdominal pain
–  Heart Palpitations
–  Anxiousness
–  Nausea
–  Confusion
–  Agitation
–  Difficulty breathing
–  Swelling of face and tongue
–  Heart Failure
–  Adrenal insufficiency
–  Coma
–  ***Acute massive overdose may be life-threatening.
–  Treatment is for symptoms and supportive.
–  Massive overdose may require beta-blockers.
–  Symptoms, following overdose, may start as quickly as 6 hours or as late as 11 days after ingestion.