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Eltroxin NZ

What is hypothyroidism
(underactive thyroid) and what causes it?

The thyroid is a small butterfly-shaped gland located in your neck and it makes two hormones tri-iodothyronine (T3) and thyroxine (T4). These thyroid hormones help your body to use energy, stay warm and keep the heart, brain, muscles, and other organs working as they normally would.

When the thyroid gland doesn’t produce enough thyroid hormones, many of the body’s functions are slowed down and affected.

The symptoms of hypothyroidism are non-specific, mild at first and are often put down to other factors such as “getting old”, stress or workload. More symptoms can develop overtime. They can include:

Weight Gain


Cold Intolerance

Irregular Menstrual Periods

Joint or muscle



Hair Loss

Puffy Pale

Dry Flaky

What Causes Hypothyroidism?

An underactive thyroid can be caused by a few different things:

This autoimmune condition causes the body’s immune system to attack and destroy the cells of the thyroid gland. It is the most common cause of underactive thyroid.
Lack of enough iodine in your diet can affect the production of the hormones.
This is when the thyroid is removed, or you might have had radiotherapy that has affected the thyroid gland.
If the pituitary gland is not working properly.
Some medications can affect the production of certain hormones. Your doctor can tell you if any medications are likely to be affecting you.

A number of women will develop an underactive thyroid while they are pregnant or after baby is born. You can learn more about that here.

For many people hypothyroidism is a life-long condition. Your doctor should be able to tell you what has caused it and how treatment with Eltroxin can help.