Levothyroxine (By Mouth)

Levothyroxine (lee-voe-thye-ROX-een)

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

Brand Name(s):

Synthroid, Levoxyl, Levothroid, Unithroid
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.

How to Use This Medicine:

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.

If a dose is missed:

• Take your medicine as soon as you remember that you missed a dose.
• Skip the missed dose if it is almost time for your next 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.
• Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.
• 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.

• If you are taking cholestyramine (Questran®), take it either 4 hours before or 4 hours after you take levothyroxine.

Warnings While Using This Medicine:

• Talk with your doctor before taking levothyroxine if you have heart disease, high blood pressure, or diabetes
• Do not change brand names of levothyroxine, unless you talk to your doctor. Look at your tablets when you get your prescription refilled. If these tablets are a different color or size than before, check with your pharmacist.
• Do not stop taking this medicine without first checking with your doctor.

Possible Side Effects While Using This Medicine:

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

• Skin rash or hives with intense itching
• Shortness of breath or trouble breathing
• Chest pain
• Severe irritability or nervousness, tremors
• Fast or irregular heartbeat
• Severe diarrhea or intense sweating

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

• Anxiety
• Headache
• Trouble sleeping
• Appetite changes, weight loss
• Menstrual irregularities

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