Generic
Name: Levothyroxine Tablets (lee-voe-thigh-ROX-een)
Brand Name: Examples include Levoxyl and Synthroid
Levothyroxine should not be used either alone
or with diet pills to treat obesity or for
weight loss because serious, even life-threatening,
effects could occur. Large doses of Levothyroxine
, especially with diet pills, may cause symptoms
of toxicity.
Levothyroxine is used for:
Treating low thyroid activity and treating
or suppressing different types of goiters.
It is also used with surgery and other medicines
for managing certain types of thyroid cancer.
Levothyroxine is a thyroid hormone. Thyroid
hormones are produced and released by the thyroid
gland and regulate the body's metabolism. When
the thyroid gland is underactive (hypothyroidism)
it does not produce enough thyroid hormone
and metabolism slows.
Do NOT use Levothyroxine if:
you are allergic to any ingredient in Levothyroxine
you have a history of heart attack, chest pain (angina), adrenal gland problems,
or elevated thyroid hormone levels that have not been treated
Contact your doctor or health care provider
right away if any of these apply to you.
Before using Levothyroxine :
Some medical conditions may interact with
Levothyroxine . Tell your doctor or pharmacist
if you have any medical conditions, especially
if any of the following apply to you:
if you are pregnant, planning to become
pregnant, or are breast-feeding
if you are taking any prescription or nonprescription medicine, herbal preparation,
or dietary supplement
if you have allergies to medicines, foods, or other substances
if you have heart problems, high blood pressure, blood clotting problems,
diabetes, bone loss (osteoporosis), digestion or nutrient absorption problems,
infertility problems, pituitary gland problems, high thyroid levels, or other
thyroid problems
If you have just had or are scheduled for surgery
Some MEDICINES MAY INTERACT with Levothyroxine
. Tell your health care provider if you are
taking any other medicines, especially any
of the following:
Aluminum salts (eg, antacids), aminoquinolones
(eg, chloroquine), amiodarone, HMG-CoA reductase
inhibitors (eg, simvastatin), iron salts (eg,
ferrous sulfate), raloxifene, rifampin, sertraline,
or sucralfate because they may decrease Levothyroxine
's effectiveness
HMG-CoA reductase inhibitors (eg, simvastatin) or tricyclic antidepressants
(eg, amitriptyline) because side effects such as nervousness, fast heart rate,
or irregular heartbeat may occur
Anticoagulants (eg, warfarin) or ketamine because their actions and the risk
of their side effects may be increased by Levothyroxine
Beta-blockers (eg, metoprolol) or digitalis glycosides (eg, digoxin) because
their effectiveness may be decreased by Levothyroxine
This may not be a complete list of all interactions
that may occur. Ask your health care provider
if Levothyroxine may interact with other medicines
that you take. Check with your health care
provider before you start, stop, or change
the dose of any medicine.
How to use Levothyroxine :
Use Levothyroxine as directed by your doctor.
Check the label on the medicine for exact dosing
instructions.
Take Levothyroxine on an empty stomach
at least 1 hour before or 2 to 3 hours after
eating. It is recommended that you take your
dose 1 hour before breakfast unless otherwise
directed by your doctor.
Take Levothyroxine with a full glass of water (8 oz/240 mL).
Notify your health care provider if you eat foods that contain soybean flour
(infant formula), cottonseed meal, walnuts, or dietary fiber. These foods decrease
the absorption of Levothyroxine . Your doctor may need to change your dose
of Levothyroxine .
Take Levothyroxine 4 hours apart from calcium supplements, iron, antacids
(those containing aluminum, calcium, or magnesium), simethicone, cholestyramine,
colestipol, sucralfate, or sodium polystyrene sulfonate. These medicines may
decrease the absorption of Levothyroxine into your bloodstream. Levothyroxine works best if it is taken at the same time each day.
It may take several weeks (4 to 6 weeks) before you notice an improvement
in your symptoms.
Levothyroxine will usually have to be taken for life, except in the cases
of temporary low thyroid activity associated with thyroid inflammation and
in patients who are taking Levothyroxine on a trial basis.
For children or patients who cannot swallow whole tablets: Crush the tablet
and mix in 1 or 2 teaspoons (5 or 10 mL) of water, and give using a spoon or
dropper as soon as possible after preparation. Do not store the mixture for
later use. Do not mix crushed tablets in soybean infant formula. Consult your
pharmacist for more information.
If you miss a dose of Levothyroxine and you are taking it regularly, take
it as soon as possible. If several hours have passed or if it is nearing time
for the next dose, do not double the dose to catch up, unless advised by your
health care provider. Do not take 2 doses at once.
Ask your health care provider any questions
you may have about how to use Levothyroxine
.
Important safety information:
Levothyroxine may rapidly swell and disintegrate
resulting in choking, gagging, the tablet getting
stuck in your throat, or difficulty swallowing.
It is very important that you take the tablet
with a full glass of water. Most of these problems
disappeared when levothyroxine tablets were
taken with water.
Tell your doctor or dentist that you take Levothyroxine before you receive
any medical or dental care, emergency care, or surgery.
If you are taking blood thinners at the same time as Levothyroxine , lab
tests will be required to adjust the blood thinners.
Diabetes patients - Levothyroxine may affect your blood sugar. Check blood
sugar levels closely. Ask your doctor before you change the dose of your diabetes
medicine.
Lab tests will be required to monitor therapy. Be sure to keep appointments.
Use Levothyroxine with caution in the ELDERLY; they may be more sensitive
to its effects.
Levothyroxine should be used with caution in CHILDREN; overuse may reduce
the child's final adult height. PREGNANCY and BREAST-FEEDING: It is not known if Levothyroxine can cause
harm to the fetus. If you become pregnant, contact your doctor. You will need
to discuss the benefits and risks of using Levothyroxine while you are pregnant.
Levothyroxine is found in breast milk. If you are or will be breast-feeding
while you use Levothyroxine , check with your doctor. Discuss any possible
risks to your baby.
Possible side effects of Levothyroxine :
All medicines may cause side effects, but
many people have no, or minor, side effects.
Check with your doctor if any of these most
COMMON side effects persist or become bothersome:
Anxiety; diarrhea; flushing; mood swings;
muscle weakness; partial, temporary hair loss;
sleeplessness; stomach cramps; tiredness; vomiting.
Seek medical attention right away if any of
these SEVERE side effects occur:
Severe allergic reactions (rash; hives; itching;
difficulty breathing; tightness in the chest;
swelling of the mouth, face, lips, or tongue);
changes in appetite; changes in menstrual periods;
chest pain; difficulty breathing; excessive
sweating; fast heartbeat; fever; headache;
hives or skin rash; hyperactivity; inability
to handle warm or hot room/weather conditions;
irregular heartbeat; irritability; leg cramps;
nervousness; pounding in the chest; seizures;
shortness of breath; tremors; weight gain or
weight loss.
This is not a complete list of all side effects
that may occur. If you have questions or need
medical advice about side effects, contact
your doctor or health care provider. You may
report side effects to the FDA at 1-800-FDA-1088
(1-800-332-1088) or at http://www.fda.gov/medwatch.
If OVERDOSE is suspected:
Contact 1-800-222-1222 (the American Association
of Poison Control Centers), your local poison
control center (http://www.aapcc.org/findyour.htm),
or emergency room immediately. Symptoms may
include chest pain; coma; confusion; disorientation;
excessive sweating; extreme nervousness; headache;
heart attack; increased bowel motility; irregular
heartbeat; irritability; menstrual irregularities;
seizures; shock; tremor.
Proper storage of Levothyroxine :
Store at room temperature, between 59 to 86
degrees F (15 to 30 degrees C), in a tightly
closed container. Protect from heat, light,
and moisture. Do not store in the bathroom.
Keep Levothyroxine out of the reach of children
and away from pets.
General information:
If you have any questions about Levothyroxine
, please talk with your doctor, pharmacist,
or other health care provider.
Levothyroxine is to be used only by the patient for whom it is prescribed.
Do not share it with other people.
If your symptoms do not improve or if they become worse, check with your
doctor.
This information is a summary only. It does
not contain all information about this medicine.
If you have questions about the medicine you
are taking or would like more information,
check with your doctor, pharmacist, or other
health care provider. |
