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“Hypo” means low or under what is normal, whereas “hyper” means high or above what is normal. 
So hypothyroidism means the thyroid is underactive and hyperthyroidism means the thyroid is overactive.
Most cases of hypothyroidism are caused by Hashimoto’s thyroiditis – an autoimmune disease that causes the immune system to damage or destroy the thyroid gland.
Other causes include;
  • Surgical removal of the gland due to cancer or another disorder
  • Congenital abnormality whereby a baby is born without a properly functioning thyroid gland.
  • Viral or bacterial infections - these can temporarily depress or stop hormone production in the thyroid. Sometimes this can become permanent.
  • Medications - some medications can induce temporary hypothyroidism.
  • Iodine deficiency - a diet severely deficient in iodine can lead to hypothyroidism.
Yes, hypothyroidism resulting from the autoimmune disease Hashimoto’s thyroiditis does run in families. Additionally, a family history of autoimmune diseases, including rheumatoid arthritis (chronic inflammation of the joints in the hands and feet), pernicious anaemia (low red blood cells), type 1 diabetes, lupus or other autoimmune diseases, increases the risk of hypothyroidism in offspring.
Unexplained weight gain or an inability to lose weight, often despite a decrease in appetite, may be a symptom of hypothyroidism. This is because hypothyroidism causes your metabolism to slow down. If you’ve been having a difficult time losing weight, check to see if you have other symptoms of hypothyroidism and see your doctor.

Hypothyroidism can be diagnosed with a simple blood test called a TSH test. If you suspect you have hypothyroidism, make a note of your symptoms and talk to your doctor.

Hypothyroidism cannot be cured, but it can be controlled. 

Treatment of hypothyroidism is best accomplished using levothyroxine such as Synthroid. 
This synthetic form of the thyroid hormone T4 is an effective treatment for most people with hypothyroidism.

It is usually recommended that it be taken in the morning, thirty minutes before eating. 

Other medications containing iron or antacids should be avoided as they can interfere with absorption of the thyroxine sodium.

     Reference: Hypothyroidism:  Understanding the disease and its symptoms. Available at Accessed November 2016.

Synthroid® (levothyroxine sodium, USP) 25mcg, 50mcg and 100mcg tablets. Prescription medicine used as a replacement or supplemental therapy in patients of any age or state (including pregnancy) with hypothyroidism, or as a pituitary TSH suppressant in the treatment or prevention of various types of euthyroid goiters. Do not use Synthroid® if you have an allergy to thyroid hormones or any of the ingredients in the tablet or have suffered a heart attack. Medicines have benefits and some may have risks. Tell your doctor if you are pregnant, plan to become pregnant or are breastfeeding. You should tell your doctor if you are taking any other medicines including those you may have purchased from a pharmacy, supermarket or health food shop as these may affect the way Synthroid® works. Possible side effects are increased pulse & blood pressure, heart problems including heart failure, heart attack and angina, difficulty breathing and tiredness, headache, sleep disturbance, mood changes, diarrhoea, vomiting, stomach cramps, increased appetite, weight loss, fever, excessive sweating, hair loss, muscle tremor and weakness, menstrual irregularities, impaired fertility, seizures. Always read the label carefully and use strictly as directed. If symptoms persist or you have side effects, see your health professional. For further information, ask your health professional or view the Consumer Medicine Information at Synthroid®; is a fully funded prescription medicine. Normal doctor’s fees and pharmacy charges apply. Ask your doctor if Synthroid®; is right for you. Synthroid®; is a registered trademark of Mylan Healthcare GmbH. Mylan NZ Ltd., Auckland. TAPS NA8758.

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