Brand Name

Synthroid {Abbott Laboratories}

Generic Name

levothyroxine, pronounced LEE voe thye ROX een

 

What is Synthroid?

Synthroid is a medication that is used to help regulate your metabolism. It replaces a hormone that would normally be produced in your thyroid gland. If your body cannot produce enough of this hormone on its own you may feel the effects of low energy or weight gain. Your doctor will test your thyroid hormone levels and may prescribe Synthroid as a supplement or replacement for the hormone produced by the thyroid gland.

Synthroid is used to treat hypothyroidism, or low thyroid hormone, or goiter, which is an enlarged thyroid gland possibly caused by hormone imbalances, or used when the thyroid gland has been damaged or removed due to radiation treatment, surgery, or cancer.

Synthroid may also be prescribed for purposes not listed in this medication guide.

 

Key Facts About Synthroid

Synthroid should never be used to treat obesity or weight problems.

If you use insulin or take diabetes medications you may need a dose change when taking
Synthroid. Your doctor will tell you how to manage your medications.

Pregnancy/breastfeeding: As Synthroid replaces a normal hormone in the body it is not
expected to harm an unborn baby. Do not stop taking this medication if you do become pregnant
while taking Synthroid. Contact your doctor for advice. If you have a low thyroid hormone level
during pregnancy it could harm both you and your baby. It is likely that your doctor will adjust
your dose during pregnancy. Synthroid can pass into breast milk, but it is not expected to be
harmful to a nursing baby. Tell your doctor if you are breast-feeding in case your doctor needs
to adjust your dose.

In many cases you will need to take Synthroid for the rest of your life. Synthroid may
increase your risk of bone loss or osteoporosis when used over long periods of time. Talk with
your doctor about ways to strengthen your bones and follow an exercise and diet regimen for bone
health.

Do not change your dose of Synthroid or switch to a generic form of levothyroxine without
first asking your about it. Different brands of levothyroxine may not work the same as Synthroid.
If you pick up your Synthroid prescription and your new pills look different tell your pharmacist
or doctor.

Certain foods may cause your body to absorb less Synthroid. These include infant soy formula,
cotton seed meal, walnuts, and high-fiber foods.

 

Before You Take Synthroid

DO NOT use Synthroid if you are allergic to levothyroxine .

Certain health issues may make taking Synthroid unsuitable for you. Discuss your use of
Synthroid with your doctor if you have any of the following:

• thyrotoxicosis,
• heart disease,
• coronary artery disease,
• or a history of blood clots or
• diabetes.
• anemia
• Uncontrolled or untreated Pituitary
• or adrenal gland issues

If you have recently had a heart attack, or are having any symptoms of a heart attack like
chest pain or a heavy feeling, pain spreading to your arm or shoulder, nausea, sweating, or a
general ill feeling you may not be a candidate to take Synthroid.

Synthroid may be affected by certain every day medications or supplements. You should avoid
taking the following supplements within 4 hours before or 4 hours after taking Synthroid to
reduce the chance that they will make your dose less effective:

• antacids that contain aluminum (Amphojel, Gaviscon, Maalox, Mylanta, Riopan, Rulox,
• Tums)
• calcium carbonate (Caltrate, Citracal, Oystercal)
• Iron supplements
• Medications that may interfere with Synthroid include:
• cholesterol-lowering drugs cholestyramine (Questran) and colestipol (Colestid)
• sodium polystyrene sulfonate (Kayexalate, Kionex)
• sucralfate (Carafate)

Tell your doctor if you are currently taking any of the products listed above.

Be sure to tell your doctor if you have recently received radiation therapy with iodine like
I-131.

 

Synthroid Drug Interactions

You should inform your doctor if you are taking any of the following:

• aspirin
• Crestor (rosuvastatin)
• Cymbalta (duloxetine)
• Fish Oil (omega-3 polyunsaturated fatty acids)
• hydrochlorothiazide
• Lasix (furosemide)
• Lipitor (atorvastatin)
• lisinopril
• metformin
• metoprolol
• multivitamins
• Nexium (esomeprazole)
• omeprazole
• Plavix (clopidogrel)
• prednisone
• Zocor (simvastatin)
• Singulair (montelukast)
• Vitamin D3 (cholecalciferol)
• Xanax (alprazolam)

Other drugs you take that are not listed may interact with Synthroid. You should tell your
doctor about all of the medications you use. This includes prescription drugs, vitamins,
supplements and herbal products, and over the counter medications. You should not begin taking a new medication without telling your doctor first.

 

Directions for Taking Synthroid

Synthroid should be taken as a medication once daily, on an empty stomach (30 minutes before
first food), first thing in the morning with plenty of water.

You should take Synthroid exactly as your doctor prescribes it. Your doctor may test your
hormone levels and change your dose to make sure you get the best results from Synthroid. You
should follow the instructions on your prescription label and not take Synthroid for longer than
recommended by your doctor, or in larger or smaller doses.

Synthroid should be taken with a full glass (8 ounces) of water. The Synthroid tablet can
dissolve very quickly may swell in the throat, possibly causing you to choke or gag.

It may take a few weeks before you start to respond to Synthroid. You should not stop taking
this medication suddenly.

Synthroid needs to be stored at room temperature, and away from light, moisture and heat.

If you miss a dose of Synthroid you should attempt to take the missed dose as soon as you
remember. However, if it is almost time for your next scheduled dose do not take the missed dose in addition to your regular dose.

 

Synthroid Side Effects

Seek medical assistance if:

if you experience any of the following adverse effects you should stop taking Synthroid and
seek emergency medical help immediately;

• allergic reaction signs, like breathing difficulties, hives and swelling of your face,
• lips, throat or tongue
• appetite and weight changes
• fever
• hot flashes
• insomnia
• irritability or nervousness
• menstrual period changes
• pounding heartbeats or fluttering in your chest
• sweating (extreme)

Less serious side effects of Synthroid may include mild hair loss.

It should be noted that this is not a complete list of possible side effects of Synthroid. You
should contact your physician for a complete list and medical advice regarding these effects.

 

Synthroid Description and Dosing

Synthroid tablets are dosed in micrograms (mcg). They are round, color coded, scored debossed
with “Synthroid” on one side and the potency on the other side. The list of tablet colors with
dosages is as follows:

25 mcg- orange

• 50 mcg- white
• 75 mcg- violet
• 88 mcg- olive
• 100 mcg- yellow
• 112 mcg- rose
• 125 mcg- brown
• 137 mcg- turquoise
• 150 mcg- blue
• 175 mcg- lilac
• 200 mcg- pink
• 300 mcg- green

Synthroid is dosed based on individual conditions and situations. You should consult your
doctor for specific dosing pertaining to you. Do not attempt to alter or change your dose without
your physician’s consent.

If you suspect that you have overdosed with Synthroid you should seek emergency help
immediately.

 

Ingredients in Synthroid

The primary active ingredient in Synthroid is levothyroxine sodium. Inactive ingredients
include acacia, confectioner’s sugar (contains corn starch), lactose monohydrate, magnesium
stearate, povidone, and talc. Each tablet also contains inactive ingredients based on their
colors:

25 mcg- FD&C Yellow No. 6 Aluminum Lake

50 mcg- no additional ingredients

75 mcg- FD&C Red No. 40 Aluminum Lake, FD&C Blue No. 2 Aluminum Lake

88 mcg- FD&C Blue No. 1 Aluminum Lake, FD&C Yellow No. 6 Aluminum Lake, D&C Yellow
No. 10 Aluminum Lake

100 mcg- D&C Yellow No. 10 Aluminum Lake, FD&C Yellow No. 6 Aluminum Lake

112 mcg- D&C Red No. 27 & 30 Aluminum Lake

125 mcg- FD&C Yellow No. 6 Aluminum Lake, FD&C Red No. 40 Aluminum Lake, FD&C Blue
No. 1 Aluminum Lake

137 mcg- FD&C Blue No. 1 Aluminum Lake

150 mcg- FD&C Blue No. 2 Aluminum Lake

175 mcg- FD&C Blue No. 1 Aluminum Lake, D&C Red No. 27 & 30 Aluminum Lake

200 mcg- FD&C Red No. 40 Aluminum Lake

300 mcg- D&C Yellow No. 10 Aluminum Lake, FD&C Yellow No. 6 Aluminum Lake, FD&C
Blue No. 1 Aluminum Lake

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