Please see Full Prescribing
Info & BOXED WARNING

IMPORTANT SAFETY INFORMATION AND USE

IMPORTANT SAFETY
INFORMATION

  • Thyroid hormones,
    including SYNTHROID,
    should not be used either
    alone or in combination
    with other drugs for the
    treatment of obesity or
    weight loss. In patients with
    normal thyroid levels, doses
    of SYNTHROID used daily
    for hormone replacement
    are not helpful for weight
    loss. Larger doses may
    result in serious or even
    life-threatening events,
    especially when used in
    combination with certain
    other drugs used to reduce
    appetite.
  • Do not use SYNTHROID
    if you have uncorrected
    adrenal problems.
  • Use SYNTHROID only as
    ordered by your doctor.
    Taking too much or too
    little SYNTHROID may
    lead to negative effects on
    growth and development,
    heart function, bone health,
    reproductive function,
    mental health, digestive
    function, and changes in
    blood sugar and cholesterol
    metabolism in adult or
    pediatric patients.
  • Taking too much
    levothyroxine may affect
    your heart, especially if you
    are elderly or have heart
    disease. Tell your doctor
    immediately if you have
    any signs of increased
    heart rate, chest pain, or an
    irregular heartbeat.
  • Tell your doctor about any
    other medical conditions
    you may have, especially
    heart disease, diabetes,
    blood clotting problems,
    and adrenal or pituitary
    gland problems. The dose
    of other drugs you may
    be taking to control these
    conditions may have to
    be changed while you are
    taking SYNTHROID. If you
    have diabetes, check your
    blood sugar levels and/or
    the glucose in your urine, as
    ordered by your doctor, and
    immediately tell your doctor
    if there are any changes.
    If you are taking blood
    thinners, your blood clotting
    status should be checked
    often.
  • Taking too much
    levothyroxine has been
    associated with increased
    bone loss, especially in
    women after menopause.
  • Tell your doctor if you are
    pregnant or breastfeeding
    or are thinking of becoming
    pregnant while taking
    SYNTHROID. Your dose of
    SYNTHROID may need to
    be increased during your
    pregnancy.
  • Tell your doctor if you start
    experiencing any of the
    following symptoms: rapid
    or abnormal heartbeat, chest
    pain, difficulty catching
    your breath, leg cramps,
    headache, nervousness,
    irritability, sleeplessness,
    shaking, change in
    appetite, weight gain or
    loss, vomiting, diarrhea,
    increased sweating,
    difficulty tolerating heat,
    fever, changes in menstrual
    periods, swollen red bumps
    on the skin (hives) or skin
    rash, or any other unusual
    medical event.
  • Partial hair loss may occur
    during the first few months
    you are taking SYNTHROID.
  • Tell your doctor if you are
    taking any other drugs,
    including prescription and
    over-the-counter products.
  • Products such as iron
    and calcium supplements
    and antacids can lower
    your body’s ability to
    absorb levothyroxine, so
    SYNTHROID should be
    taken 4 hours before or after
    taking these products.
  • Tell your doctor or dentist
    that you are taking
    SYNTHROID before any
    surgery.
  • Use SYNTHROID only as
    ordered by your doctor.
    Take SYNTHROID as a single
    dose, preferably on an
    empty stomach, one-half to
    one hour before breakfast.
  • Once your doctor has found
    your specific SYNTHROID
    dose, it is important to
    have periodic lab tests and
    clinical evaluations to assess
    your treatment response.
  • Foods like soybean flour,
    cottonseed meal, walnuts,
    and dietary fiber may
    cause your body to absorb
    less SYNTHROID from
    the gastrointestinal tract.
    Grapefruit juice may cause
    your body to absorb less
    levothyroxine and may
    reduce its effect. Let your
    doctor know if you eat
    these foods, as your dose of
    SYNTHROID may need to be
    adjusted.
  • It may take several weeks
    before you notice an
    improvement in your
    symptoms.

This is the most important
safety information you
should know about
SYNTHROID. For more
information, talk with your
doctor.

USE

SYNTHROID® (levothyroxine
sodium) tablets, for oral
use is a prescription, man-
made thyroid hormone that
is used to treat a condition
called hypothyroidism in
adults and children, including
infants. It is meant to
replace a hormone that is
usually made by your thyroid
gland. Generally, thyroid
replacement treatment is to
be taken for life. SYNTHROID
should not be used to treat
noncancerous growths or
enlargement of the thyroid
in patients with normal
iodine levels, or in cases of
temporary hypothyroidism
caused by inflammation of the
thyroid gland (thyroiditis).

You are encouraged to report
negative side effects of
prescription drugs to the
FDA. Visit www.fda.gov/
medwatch
or call 1-800-FDA-
1088.

If you are having difficulty
paying for your medicine,
AbbVie may be able to
help. Visit AbbVie.com/
PatientAccessSupport
to learn
more.

Please see the full
Prescribing Information,
including BOXED WARNING,
or visit
https://www.rxabbvie.com/
pdf/synthroid.pdf
.

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reserved. Synthroid® and
its design are registered
trademarks of AbbVie Inc.
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