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What Is Synthroid Thyroid Medication?

Learn more about how Synthroid thyroid medication compares to generic levothyroxine.
What Is Synthroid Thyroid Medication?
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The thyroid is a small gland at the base of your neck that produces hormones to regulate your body's energy use. Hypothyroidism is the condition of your thyroid gland not producing enough thyroid hormones. It is treatable in most people with thyroid hormone replacement medication and lifestyle modifications.

Read on to learn more about Synthroid, how it works, and how to get a Synthroid prescription online. 

What is Synthroid?

Synthroid is a brand-name form of levothyroxine, the thyroid hormone replacement drug used to treat hypothyroidism. As of 2019, it is the most commonly prescribed medicine in the United States, with tens of millions of prescriptions per month. Other brand-names of levothyroxine include Tirosint, Levoxyl, Unithroid, and Euthyrox.

Synthroid has 12 options of dosage to help your doctor find the dose that's right for you. Your weight, age, cause of hypothyroidism, other health conditions, and other medications you're taking all determine your dosage.

Fillers in Synthroid include lactose, cornstarch, and dyes.

How does Synthroid work?

When you have hypothyroidism, your thyroid doesn't make enough thyroid hormone (thyroxine), affecting virtually every system in your body. Synthroid helps restore adequate thyroid levels by replacing the amount of thyroxine that your body is missing. Synthroid's active ingredient is levothyroxine sodium, a human-made hormone that works in the same way as thyroxine.

Synthroid dosage and treatment

For Synthroid to work most effectively, you should take it the same way every day. The amount of medicine that you need is exact, so the way you take it can affect how much medicine your body absorbs. Always take your medication exactly as your doctor prescribes.

Typically, instructions say to take Synthroid once a day, every day at the same time before breakfast with only water and on an empty stomach. Wait 30-60 minutes before eating or drinking anything other than water.

Some foods and supplements can interfere with your absorption of Synthroid. Foods containing soy and cottonseed meal, walnuts, grapefruit, and dietary fiber can make this medication less effective. Talk with your doctor if you regularly consume these foods as they may want to adjust your dosage. 

Some supplements and medications may also affect the way Synthroid works. Take your Synthroid medication four hours before or after taking supplements or multivitamins with iron, supplements or multivitamins with calcium, or antacids. 

Clinical study of Synthroid

One study recruited 22 women with hypothyroidism to take four levothyroxine products for 6-week periods in the same dosage as their pre-study routine. The purpose was to compare Synthroid, Levoxyl, and two generic levothyroxine options. Results showed no significant difference in thyroid hormone levels between the four products.

You might choose one over the other if you experience adverse reactions to the fillers in generic levothyroxine.

Side effects of Synthroid

Side effects of Synthroid are often from overdosage, and include the following: 

  • General fatigue
  • Increased appetite
  • Weight loss
  • Heat intolerance
  • Fever
  • Excessive sweating
  • Headache
  • Hyperactivity
  • Nervousness, anxiety, or irritability
  • Difficulty sleeping
  • Tremors, muscle weakness, or muscle spasm
  • Increased pulse and blood pressure
  • Diarrhea and vomiting
  • Hair loss
  • Skin flushing or rash
  • Menstrual irregularities

If you experience any of these symptoms, talk to your doctor to adjust your medication or dosage.

Can you get Synthroid online?

To legally get a prescription for medication, you first need to consult with a doctor. Then, your doctor can send the prescription to a pharmacy to fill. Be very wary of websites that offer to sell medication without a prescription.

Paloma Health offers virtual consultations with thyroid doctors. You meet with a doctor from your computer or smartphone to get a comprehensive evaluation, diagnosis, and prescription for medications like Synthroid.

Schedule a free call with a care advisor to determine if Paloma Health might be right for you.

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Katie Wilkinson

Katie Wilkinson, previously serving as the Head of Content and Community at Paloma Health, fervently explores the nexus between healthcare and technology. Living with an autoimmune condition, she's experienced firsthand the limitations of conventional healthcare. This fuels both her personal and professional commitment to enhancing patient accessibility to superior care.

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