Thyroid Hormone

Triiodothyronine and thyroxine are the two main thyroid hormones also called the T3 and T4 hormones. They are tyrosine-based hormones which are produced by the thyroid gland and dispersed into the bloodstream, where thyroxine is more plentiful than its partner, with a ratio somewhere in the region of 20 to 1

The primary functions of thyroid hormones are many and varied, being used by every cell in the body, and playing a prominent role in the metabolism of fat, carbohydrates and proteins, as well as stimulating a good metabolic rate.

They also play a key part in protein synthesis and cell development all throughout the body. Thyroid hormone synthesis is a process which can be fairly readily either inhibited or promoted and stimulated, depending on the desired effect of the treatment and the condition of the patient, and this inhibition or stimulation can be done using either physiological or psychological methods, or both if appropriate.

Hypothyroidism is the condition in which the body experiences a deficiency in thyroid hormones which prevents various processed from functioning effectively. It can be treated effectively by supplementation of the main hormones T3 and T4, either from organic sources, or synthetically produced.

Both hormones are easily absorbed in the gut, and oral treatment using thyroid hormones is safe and preferred. The most prominent synthetic thyroid hormone is levothryoxine, which is proven safe and effective, and is specifically manufactured to be taken as a once-daily dosage, using a time-release action. Natural hormone therapy typically involves all four main thyroid hormones, usually extracted from pigs.

Around five percent of the population over the age of sixty will suffer from hypothyroidism, making it a major medical condition. The overwhelming majority of these people will receive treatment for it in the form of hormone therapy, whether synthetic or natural.

Giving birth puts a woman at increased risk of developing hypothyroidism, with about 5% of women suffering it to some extent in the year following their pregnancy. Somewhere in the region of one in five of women who suffer postnatal hypothyroidism will experience the condition long-term.

Cases of hypothyroidism are confirmed by means of blood tests before thyroid hormones can be prescribed, most often in pill or tablet form, and usually in the form of levothyroxine under one of its many trade names, such as Levoxl, Levaxin, Eltroxin, Synthroid and Thyrax. Generic versions of the drug levothyroxine are also available, sometimes under the name L-thyroxine. These medications should be taken shortly before mealtimes and with water in order to maximize the absorption of the drug and thereby maximize its effectiveness.

Some foodstuffs and other products are known to have an inhibiting effect on the action of thyroid hormone replacement therapies, and should be avoided if possible while a patient is undergoing a course of thyroid hormone therapy. Offending substances are any supplements or foods with a high iron or calcium content (such as milk) and any and all soy products.

Some patients may experience side-effects as a result of thyroid hormone replacement treatments, including headaches, anxiety, loss of weight and insomnia, as well as shaking and sweating, and the sensation of an accelerated or irregular heartbeat.

A small number of people may also be allergic to some or all forms of thyroid hormone replacements, and may experience severe symptoms of nausea, shortness of breath and breathing difficulties, as well as pronounced swelling of the face and tongue. In these circumstances, medical assistance should be sought as a matter of urgency.

Thyronamines have not yet been developed for clinical use, but they may have a role to play in stimulating the brain to enter a semi-shutdown state by mimicking the onset of hypothermia. This might be of particular use in limiting the damage caused by ischemic shock.

Hyperthyroidism is the opposite of hypothyroidism, and occurs when the thyroid gland is overactive. Possible treatments for this condition include the antithyroid drugs propylthiouracil and methimazole, whose brand name is Tapazole. Antithyroid drugs are a temporary solution to the condition, and further medical treatment will be required if it does not settle down, including possible treatment with radioactive iodine.

Sufferers of thyroid cancer may need to stop taking levothyrozine temporarily in oder that safe and accurate diagnostic tests may be carried out. In this case, both thyrogen and thyrotropin may be substituted, which will temporarily relieve symptoms of hypothyroidism without altering test results. These drugs are developed specifically and exclusively for this purpose.