Levothyroxine - Synthetic T4
There are three funded Levothyroxine medications on the Pharmaceutical Register.
Eltroxin by GlaxoSmithKline - new formulation
Goldshield, or Forley's Levothyroxine and
Synthroid by Abbott Pharmaceuticals in Canada.
Also available at some pharmacies are other options -
Eutroxsig - Sigma in Australia, Almus and Teva. These versions are not funded and will cost you.
It pays to check with pharmacies before submitting your prescription, as they may not stock the particular variety you prefer.
It is recommended that when you go onto an alternative levothyroxine, you start with a reduced dose of 50% (half) your usual dose of Eltroxin.
1/2 normal dose for 10 days
3/4 normal dose for 10 days
full dose for 10 days
then request a new set of blood tests from your doctor.
There is a possibility that you may not need as high a dose as on the Eltroxin.
Whole Thyroid Extract - Dessicated Porcine Gland
For over 100 years dessicated pig’s gland was used successfully as the treatment for Hypothyroidism. In the 1970’s it was usurped by synthetic T4-only medications and doctors ceased to be trained in it's use.
Whole Thyroid (Thyroid USP) is standardised whole desiccated porcine gland which contains a combination of thyroid hormones and their precursors i.e. Thyroxine (T4), Triiodothyronine (T3), Diiodothyronine (T2), and Monoiodothyronine (T1) as well as calcitonin and any other hormones usually present in the thyroid.
Desiccated thyroid extract can be used by itself, as a complete thyroid hormone replacement treatment or in combination with synthetic T4 or T3 to alter the ratio of T4 to T3. The ratio of T3 to T4 is fixed at approximately 1:4, so it can't be adjusted unless T4-only or T3-only pills are taken as well.
Although Thyroxine (T4) is still the standard treatment for hypothyroidism, many studies had proven that the combination of T3 & T4 is a much better way of addressing hypothyroidism. Thyroxine (T4) is a prohormone for triiodothyronine (T3) as it is converted to the active T3. T3 is the dominant hormone in all body cells. It exerts the thyroid function in the different body organs with the predominant action on the brain, enhances long term memory and reduces anxiety. Patients on the combination therapy have reported that it improves the feeling of well being. In addition, this therapy has been shown to improve mood and alleviate depression.
In contrast, research shows that treatment with T4 alone does not improve cognition and psychological wellbeing. T3 may also improve memory and help weight loss. Studies are underway into the functions of T2 & T1.
Currently in New Zealand there is no consented medicine containing Whole Thyroid.
This medication can be compounded on prescription and supplied in accordance with Section 29 of the Medicines Act and Regulation 44 of the Medicines Regulations.
APPROX. CONVERSION GUIDE:
|Standard [USA]||Whole Thyroid||Synthetic Thyroxine|
|1/4 grain||15/16.25 mg Thyroid USP||25 mcg Levothyroxine [T4]|
|1/2 grain||30/32.5 mg Thyroid USP||50 mcg Levothyroxine [T4]|
|1 grain||60/65 mg Thyroid USP||100 mcg Levothyroxine [T4]|
Save Natural Thyroid
The US manufacture of Natural Thyroid medication may be under threat. Mary Shomon is on the case and has started the Save Natural Thyroid Coalition. If you join the yahoo group, don't forget to filter your emails into a folder, or choose the option of reading on the web - there is a lot of traffic on the group.
Liothyronine - synthetic T3
In New Zealand, T3 can be prescribed but is not funded by Pharmac. Tertroxin made by Goldshield Pharmaceuticals.
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Carbimazole - funded
Also known as Methimazole
Inhibits the synthesis of thyroid hormones by blocking the oxidation of iodine in the thyroid gland, blocking iodine's ability to combine with tyrosine to form thyroxine and triiodothyronine (T3), does not inactivate circulating T4 and T3.
Propylthiouricil - not funded
In general, propylthiouracil is considered second-line therapy to Carbimazole, except in cases of allergy or intolerance to methimazole or in patients with Graves' disease in their first trimester of pregnancy. Avoid use of propylthiouracil in pediatric patients unless no other treatment options are available. Users should be aware of possible signs or symptoms of hepatotoxicity (eg, fatigue, loss of appetite, weakness, yellowing of eyes or skin); and be monitored for a minimum of 6 months after propylthiouracil initiation; and discontinue propylthiouracil if liver injury is suspected.
The United States Food and Drug Administration (FDA) has added a Boxed Warning to the label for propylthiouracil, to
include information about reports of severe liver injury and acute liver failure, some of which
have been fatal, in adult and pediatric patients using this medication.
The new warning also states that for patients being started on treatment for hyperthyroidism, it may be appropriate to reserve use of propylthiouracil for those who cannot tolerate other treatments such as methimazole, radioactive iodine or surgery. In addition, due to the occurrence of birth defects that have been observed with the use of methimazole during the first trimester of pregnancy, propylthiouracil may be the treatment of choice during and just before the first trimester of pregnancy.
For additional information for healthcare professionals, including the data summary, please visit the FDA's website
Medicines Act 1981
Section 25 permits practitioners to procure for sale or supply any medicine for a particular patient in their care.
Section 29 enables a New Zealand company to obtain and supply an unapproved medicine when authorised by a prescriber.
Unapproved use of medications
New Amendments to the Medicines Regulations 1984