What Is Synthroid Used For? Everything You Need to Know

Category: Drug Information


Posted on December 25, 2019

Vanessa is a health writer and blogging expert. Her specialities are medicine, health and wellness. She is proud to call Vancouver, BC her home where she enjoys the ocean and mountains with her dog Mr. ChowChow.


With so many medications available, it’s sometimes challenging to keep them all straight. Sure, healthcare workers must become familiar with prescription drugs. But what happens if you have no experience working in the medical field and you need to begin taking a common medication like Synthroid?

If you’ve recently been prescribed the medication Synthroid and you’re unsure about its usage, dosage, and side effects, there’s no need to worry.

We’ve compiled the information about Synthroid for you.

Sit back and settle in to learn the benefits of taking this effective drug.

What is Synthroid?

Synthroid is the brand name for Levothyroxine, a thyroid medication.

What Does Synthroid Treat?

Synthroid replaces the hormone T4, which is produced by the thyroid gland with levothyroxine sodium. The medication treats Hypothyroidism (underactive thyroid gland), enlarged thyroid gland (goiter), and thyroid cancer.


Hypothyroidism occurs if the thyroid gland doesn’t make enough hormones according to Medical News Today. The thyroid gland is part of the endocrine system. Thyroid hormones help the body regulate metabolism. When thyroxine levels decrease, the body struggles to function.

Since thyroid hormones impact many organ systems in the body, there are numerous symptoms which include:

  • Fatigue
  • Constipation
  • Difficulty tolerating hot or cold
  • Dry skin
  • Insomnia
  • Depression
  • Loss of Libido
  • Infertility issues
  • Brain Fog

When left untreated Hypothyroidism causes significant problems to your body. It can make it difficult to function at school, work, or activities once loved.


A Goiter develops when the thyroid gland becomes enlarged. Goiters don’t cause pain, but a patient might develop a cough or difficulty swallowing according to the MayoClinic.

Other symptoms might include hoarseness, trouble breathing, or tightness in the throat.

Goiters form due to lack of iodine in the diet, overproduction, or underproduction of thyroid hormone. The type of treatment received depends on whether the goiter is small or large.

Getting an examination from your doctor is best if you suspect a goiter is present.

Thyroid Cancer

Thyroid Cancer develops in four forms, Papillary, Follicular, Medullary, and Anaplastic. Papillary is a form of thyroid cancer and appears in 70 – 80 percent of thyroid cancer patients. It grows slowly and might spread to the lymph nodes.

Follicular accounts for 10 – 15 percent of thyroid cancer and could spread to the lungs and bones. Medullary impacts two percent of thyroid cancer patients and is considered hereditary. Anaplastic is the most advanced form of thyroid cancer and doesn’t respond well to treatment.

Treatment for thyroid cancer includes medication, radioactive iodine therapy, and surgery.

How Often Can I Take It?

Take Synthroid once a day, every day, around the same time, at least 30 minutes to one hour before breakfast. Ingest the pill with a full cup of water on an empty stomach, according to Synthroid.com.

Please wait at least four hours before taking antacids, calcium supplements, or iron supplements because they might interfere with how the pill works.

Certain foods like fiber, grapefruit, and walnuts might make Synthroid less effective.

If you miss a dose of your Synthroid, please speak to your doctor for more information.

Synthroid Dosages

Synthroid comes in many dosages for the treatment of hypothyroidism and other thyroid-related disorders. The dosages range from 25 mcg – 300 mcg. The pills are colored to help you recognize the amount of medication.

Do not take more than you prescribed dosage and continue taking until your doctor tells you to stop.

It might take several weeks for your thyroid levels to stabilize. Continue taking your Synthroid daily and check with your doctor if you have concerns or questions.

Synthroid and Pregnancy

Being pregnant is a special time for a woman. But if she has Hypothyroidism, the pregnancy could develop more issues, according to Everyday Health.

Thyroid hormones help control the body’s metabolism and functions. When you’re meant to produce hormone for two lives, it can put a strain on your body, thus putting your baby’s cognitive development at risk.

But it can also cause pre-eclampsia, muscle pain or weakness, anemia, and placenta abnormalities.

This is why treating Hypothyroidism is essential during pregnancy. If a family history of Hypothyroidism exists, then talk with your OB/GYN. Blood tests can reveal if you have low thyroid hormone levels.

If you do have Hypothyroidism, expect your doctor to monitor your levels through testing.  The dosage of your Synthroid might increase as the pregnancy continues.

After the delivery of your baby, your Synthroid dosage might decrease, but you will need to remain on it, especially if you’re breastfeeding. Synthroid is safe to take during pregnancy and breastfeeding.

But be sure to take your Synthroid at least four hours before taking your prenatal vitamins, which might contain calcium and iron.

What Are The Side Effects of Synthroid?

Taking Synthroid is helpful for people suffering from Hypothyroidism. But it might cause side effects too. Common side effects of Synthroid include abnormal heartbeat, change in appetite, changes in the menstrual cycle, chest pain, headache, leg cramps, weight loss or gain, and irritability.

If you suffer from other medical conditions like diabetes, heart disease, blood clots, speak with your doctor about taking Synthroid with other medications.

Certain prescription drugs might cause the Synthroid not to work or cause side effects.

Fill Your Prescription

Synthroid offers many benefits for people with a thyroid disorder. If taken every day, it replaces the thyroid hormone and allows the patient to feel better. If you think you might have Hypothyroidism, schedule a doctor’s appointment.

To learn more about placing your order with us, please visit our website for more information.

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