Thyroid supplement (By mouth)

Treats hypothyroidism (the body does not produce enough thyroid hormone).

Brand Name(s):

Adthyza, Armour Thyroid, Cytomel, Euthyrox, Levoxyl, NP Thyroid, NP Thyroid 120, NP Thyroid 15, NP Thyroid 60, NP Thyroid 90, Nature-Throid, Synthroid, Thyrolar, Unithroid, WP Thyroid

There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

You should not use this medicine if you have had an allergic reaction to any type of thyroid hormone or if you have an overactive thyroid gland.

How to Use This Medicine:

Capsule, Tablet

  • Your doctor will tell you how much to take and how often
  • Take your medicine at the same time every day.
  • Take the medicine on an empty stomach.
  • Do not stop taking this medicine without first checking with your doctor, you may need to take smaller and smaller doses before completely stopping the medicine.

If a dose is missed:

  • Take the missed dose take as soon as possible.
  • Skip the missed dose if it is almost time for your next regular dose.
  • You should not use two doses at the same time.

How to Store and Dispose of This Medicine:

  • Store at room temperature, away from heat, light, and moisture.
  • Keep all medicine out of the reach of children.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Make sure your doctor knows if you are taking a blood thinner (Coumadin®), cholestyramine (Questran®), medicine for diabetes (insulin, Diabenese®, Glucotrol®), estrogens, birth control pills, or products used for colds, asthma, appetite control, hay fever, or sinus problems.

Warnings While Using This Medicine:

  • Check with your doctor before taking this medicine if you have heart disease, high blood pressure, diabetes, or an underactive adrenal or pituitary gland.
  • Tell your doctor if you are pregnant or breastfeeding.
  • Large doses of thyroid hormones, especially when taken with diet pills, can result in dangerous side effects.
  • Make sure you see your doctor for regular check-ups so your condition can be followed closely.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

  • Skin rash or hives
  • Shortness of breath or trouble breathing
  • Chest pain
  • Fast or pounding heartbeat
  • Inability to stand heat
  • Extreme nervousness or irritability, tremors
  • Severe diarrhea, intense sweating

If you notice these less serious side effects, talk with your doctor:

  • Anxiety
  • Headache
  • Trouble sleeping
  • Appetite changes, weight loss
  • Irregular menstrual periods

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088


Last Updated: 9/6/2024

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