The thyroid is a gland that affects many vital processes of the body including growth, energy use, and fertility. Hypothyroidism is when low production of thyroid hormones due to an underactive thyroid gland causes essential processes of the body to slow down. A number of side effects can result from this including low energy, weight gain, and depression. Hypothyroidism is an incurable condition and usually requires lifelong maintenance of symptoms with hormone replacement therapy.

While it is most common in women, hypothyroidism can also happen in men and onset can occur at any age. The condition affects almost 10 million Americans and millions more globally. Cases often go undiagnosed as symptoms can be mistakenly associated with other conditions. There are many possible causes for hypothyroidism and the exact cause may include a combination of genetic and environmental factors. Some of the reasons the condition may develop include:

• Autoimmune diseases like Hashimoto’s thyroiditis: Autoimmune diseases occur when the immune system attacks healthy cells. Hashimoto’s is a genetic autoimmune disease that is the most common cause of hypothyroidism. A goiter will almost always appear as a result of Hashimoto’s. A goiter is the thyroid gland enlarging as the demand for hormone production increases.
• Treatment of hyperthyroidism: Hyperthyroidism is an overproduction of thyroid hormones. Patients who are treated for hyperthyroidism with radioactive iodine treatments and some medications often develop hypothyroidism.
• Iodine deficiency: A diet with adequate levels of iodine is crucial to the production of T4. Iodine deficiency is a major cause of hypothyroidism in many parts of the world but is not a common cause of the condition in the United States.
• Removal of the thyroid gland: Hypothyroidism can result from complete removal of the thyroid gland due to thyroid cancer. If a patient has their entire thyroid gland removed (not just one side) they almost always will require lifelong hormone replacement therapy.
• Use of certain drugs: Patients who take lithium have an increased risk for developing hypothyroidism. Almost 1 out of 5 patients taking lithium will develop symptomatic hypothyroidism. Certain other drugs that treat epilepsy and depression may also decrease thyroid hormone levels to a point that hormone replacement is necessary.
• Imbalance of other hormones: Different kinds of hormone production are connected and an increase or decrease in one kind can affect the production of another. Estrogen and progesterone both have an impact on thyroid functioning.

Symptoms of Hypothyroidism

Since thyroid hormones affect many important processes of the body, a variety of symptoms can result when levels are too low. Some symptoms occur earlier with the onset of hypothyroidism and can be mistakenly attributed to aging or other conditions. Over time, symptoms can develop that are more severe. These are just some of the symptoms that may result from under-production of thyroid hormones:

• Fatigue
• Weakness
• Weight gain and difficulty losing weight
• Coarse, dry hair
• Goiter
• Anemia
• Dry, itchy skin
• Rough, pale skin
• Hair loss
• Cold intolerance
• Muscle cramps and aches
• Constipation
• Depression
• Irritability
• Memory loss
• Abnormal menstrual cycles
• Decreased libido

Types of Thyroid Hormones

Thyroxine (T4) is an inactive form of the hormone produced by the thyroid gland that controls the body’s energy usage.

Triiodothyronine (T3) is the active form of the T4 hormone, with the majority of T3 being produced as needed through conversion of T4 in the body. Only about 20 percent of T3 is directly produced by the thyroid gland.

Testing for Hypothyroidism

There is no way to tell for sure that symptoms are the result of hypothyroidism without a blood test. Low T4 can be detected through two blood tests: the TSH (thyroid-stimulating hormone) test and the T4 test. TSH is what stimulates the thyroid glands to produce hormones. The TSH test will determine how much T4 the thyroid gland is trying to make to compensate for the low levels in the blood. If TSH levels are high then it means T4 levels are low, as the TSH is trying to stimulate the glands to produce more T4. The other test that may be used is the T4 test, which simply measures the amount of available T4 in the blood.

TSH Testing and Hypothyroidism

TSH testing is the more common type of blood test used to diagnose hypothyroidism. The levels at which hormone replacement is considered necessary will vary between individuals. Generally accepted TSH ranges for prescribing hormone therapy are listed below.

TSH > 10mU/L – Clear indicator of hypothyroidism and the patient should start replacement therapy

TSH between 4.5-10mU/L – If the patient shows symptoms of hypothyroidism at these levels, replacement therapy is usually recommended

TSH between 0.45-4.5mU/L – Normal thyroid function usually produces results in this range

The normal range for T4 will vary between individuals and can fluctuate throughout life. That is why many healthcare providers choose a compounding pharmacy to customize hormone replacement therapy. Different amounts of T3 and T4 will be required depending on the patient’s hormone deficiency and will need to be adjusted over time. It should also be noted that the decision about whether to use hormone replacement therapy and what dosage to use is not only about hormone levels as detected through blood tests but also about managing symptoms.

Management of Symptoms with Thyroid Hormone Replacement

Hypothyroidism is not a curable condition and treatment focuses on increasing hormone levels with regular, lifelong use of hormone supplements. Replacement of T4 hormone with prescription supplements can improve symptoms of hypothyroidism in a safe and effective way. In the long term, symptoms of hypothyroidism can be well managed with the use of hormone replacement in the right dosages and with consistent monitoring.

Levothyroxine is a synthetic derivative of T4 that is most often used for thyroid hormone replacement therapy. A reduction in symptoms after starting treatment with levothyroxine can take up to six weeks. Regular monitoring of symptoms is important as fluctuations in hormones can alter the required dosage.  While many patients respond well to T4 supplements, sometimes a combination of both T4 and T3 is prescribed for patients who still exhibit symptoms after using only T4.

It is important to remember that hypothyroidism requires lifelong use of thyroid hormone replacement. Regular monitoring with a healthcare provider and consulting with a pharmacist are necessary so that dosages can be adjusted to fluctuations in hormones over time and changes in symptoms. A healthcare provider will sometimes adjust dosages of thyroid medication in very minute amounts to get the right treatment.

Commercially Available Products vs. Customized Products from a Compounding Pharmacy

Commercially available thyroid supplements are not an appropriate choice for all patients. Many healthcare providers recommend their patients work with a compounding pharmacy for treating hypothyroidism because of the customized care available. There are many reasons why choosing a compounding pharmacy for hormone replacement is preferable to obtaining a commercially produced product:

Custom dosages: At a compounding pharmacy, T3/T4 supplements are made in varied strength combinations. Hypothyroidism requires lifelong use of hormone replacement. Adjustments to dosages are often required at regular check-ups due to fluctuations in hormone levels and changes in symptoms. A compounding pharmacy has the ability to alter dosages based on these changes. This makes a compounding pharmacy an especially useful partner in the long-term care of patients with hypothyroidism.

Remove Undesirable Ingredients:  Many commercially available products contain fillers and additives that can cause problems for individuals with sensitivities to these products. Patients who need products without certain ingredients like gluten or dyes can have a custom formulation made for them by a compounding pharmacy. This is especially important since thyroid hormone capsules will be taken daily for a person’s entire life.

Combination T3/T4 Therapy: Some patients will not respond to T4 only and may have additional problems converting T4 into T3. Conversion of T4 to T3 can result from a number of factors including stress, aging, medications, and certain diseases. For patients who do not respond to a T4-only treatment, a formulation that includes both T4 and T3 can be customized by a compounding pharmacy.

Availability of Sustained Release: The commercially available versions of T3 are fast-acting and tend to leave the body within a few hours. The fast release can cause higher than necessary levels of T3 that may lead to adverse side effects. A sustained release capsule can provide release over a period of twelve hours. This particular kind of T3 capsule is not commercially available and must be made by a compounding pharmacy.

Seeking Treatment for Hypothyroidism

Hormone replacement with T4 and T3 is the only effective way to manage hypothyroidism. High-quality formulations of thyroid hormones customized by a compounding pharmacy have many benefits over commercially available supplements. Since symptoms are not always easily associated with low thyroid hormone production, it is important to see a healthcare provider who can perform blood tests and get an accurate diagnosis. Working with a compounding pharmacy, healthcare providers can help their patients easily manage their hypothyroidism throughout their lives.