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Synthroid Review

Synthroid is a prescription medication designed to treat hypothyroidism and several forms of thyroid cancer. Find out how Synthroid works and how it can help you, today.
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There are different types of prescription medication for hypothyroidism, and Synthroid is one of them. Synthroid (levothyroxine sodium), is a synthetic version of thyroxine or T4 and is designed to treat underactive thyroid disorder as well as several types of thyroid cancer. 

How Does Synthroid Work?

Synthroid is recommended for people who have low thyroid hormone production. Basically, the thyroid gland produces two kinds of thyroid hormones, Thyroxine or T4 being one of them.

T4 is a key hormone that regulates metabolic processes in the body.

Hypothyroidism or the production of low thyroid hormones occurs naturally or when the thyroid gland is injured or surgically removed.

Low production of thyroid hormones can impair the person’s mental and physical activity which explains the need to replace the hormone with synthetic versions such as this prescription medication.

How Does One Take Synthroid?

Patients with hypothyroidism usually follow a lifelong therapy, which involves taking thyroid hormone replacements for most of their lives, or as directed by a doctor.

The medication is usually taken once daily, at least thirty to sixty minutes before breakfast.

Synthroid comes in either tablet or capsule form. Capsules are recommended for older patients while tablets are recommended for infants and small children.

Synthroid comes in twelve different tablets containing different dosage strengths, which are designed to meet the different needs of each individual. The recommended dosage for Synthroid varies from one person to another, and this is based on the person's current weight, age, existing medical conditions, thyroid hormone levels, lab results and response to previous treatment.

The average dosage for Synthroid is as follows:

Synthroid Dosage
Older Adults: 1mcg per 1 kg of bodyweight

Young Adults and Teenagers: 1.7 mg per kg of bodyweight

Children 12 years and older: 2 to 3 mcg per kg of bodyweight

Children 6 to 12 years old: 4 to 5 mcg per kg of bodyweight

Children 1 to 5 years old: 5 to 6 mcg per kg of bodyweight

Infants 6 to 12 months of age: 6 to 8 mcg per kg of bodyweight

Infants 3 to 6 months of age: 8 to 10 mcg per kg of bodyweight

Infants 0 to 3 months of age: 10 to 15 mcg per kg of bodyweight 

Storing Synthroid

If you are taking Synthroid, make sure that you follow proper storage instructions. Keep your medication in between 59 to 86 degrees Fahrenheit – never in places with lower or higher temperature. Next, keep it away from sunlight or direct moisture.

Third, Synthroid should be placed in a small container that’s out of reach from small children or pets. Lastly, it should be taken within its prescribed period. Any Synthroid tablets that are unused after its expiration date should be thrown away.

What Are The Side Effects of Synthroid?

Synthroid, like any other prescription medication, can cause several side effects.

Hair loss is often noted by many users of the drug and it may occur during the first few months of treatment. Hair loss is an initial response as the body adjusts to the drug, but it eventually goes away within a couple of months.

Most people using the drug do not experience any serious side effects, but there are still cases where side effects can happen. Most serious side effects are caused by cases of over-replacement or taking too much levothyroxine.

The symptoms that are associated with over-replacement include:

  • Palpitations
  • Irregular heart beat
  • Chest pain
  • Shortness of breath
  • Mood changes such as mood swings, anxiety, nervousness
  • Shaking and tremors
  • Sensitivity to heat and sweating
  • Headache

Some very rare symptoms include:

  • Blurred, double or temporary loss of vision
  • Eye pain
  • Slow growth in children
  • Pain in the knee and hip
  • Seizures

In very rare cases, an individual may experience serious allergic reaction to Synthroid, which includes the following symptoms:

  • Rashes
  • Itching
  • Swelling (especially in the face, tongue and throat area)
  • Difficulty breathing
  • Nausea

These are just some of the common side effects associated with Synthroid. In case any of the following symptoms are noted, it is important to seek medical attention right away.

Warnings When Using Synthroid

Some medicines should not be used together, but there are also cases when two different types of drugs can be used at the same time, even if it may cause an interaction. Some types of medicine can increase the risk of side effects, so it is important to let your doctor know that you are taking them for him or her to change specific doses or take other necessary precautions.

Inform your doctor if you are taking the following: 

  • Antacids
  • Amiodarone
  • Carbamazepine
  • Calcium supplements such as Tums
  • Cholestyramine
  • Cold medications
  • Colestipol
  • Digoxin
  • Female hormones such as birth control pills
  • Herbal supplements
  • Ketamine
  • Mental depression medication
  • Phenobarbital/barbiturate medications
  • Phenytoin
  • Prednisone/corticosteroids
  • Rifabutin
  • Rifampin
  • Sucralfate
  • Soy isoflavones

Aside from specific medications, some lifestyle habits can also cause direct interactions with Synthroid, and these include smoking, use of illegal drugs and similar substances and regular consumption of alcohol and caffeine.

The presence of medical problems may also affect the results of Synthroid.

Make sure to let your doctor know beforehand if you have a history of these specific conditions: 

  • Abnormal heart rhythms
  • Adrenal gland problems
  • History of heart disease or heart attack
  • History of blood vessel disease
  • History of osteoporosis
  • Overactive thyroid

Some Precautions 

Because thyroid replacement treatments are often used throughout the patient’s whole life, regular checkups are necessary to check the progress of the treatment and determine if the medicine is indeed working. Routine check-ups usually include blood and urine tests.

Synthroid counteracts and treats infertility as a symptom of hypothyroidism. However, it should not be used as a product to solely treat infertility.

Pregnant women can take Synthroid, but will need a larger dose of levothyroxine. In case you get pregnant while on medication, tell your doctor right away so that he or she may increase the dosage.

Long-time intake of Synthroid may lead to lower bone density, which may lead to osteoporosis.

Synthroid can be taken along with different health supplements, vitamins and minerals – just make sure to let your doctor know that you are taking them or planning to take them.

Next Article: Low Triiodothyronine and Thyroxine?


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