Levothyroxine Sodium for Injection - Consumer Medicine Information
|Manufacture:||Fresenius Kabi USA, LLC|
|Condition:||Hypothyroidism, Post-Thyroidectomy (Hypothyroidism, After Thyroid Removal), Hypothyroidism, After Thyroid Removal (Hypothyroidism, Post-Thyroidectomy), Hypothyroidism (Underactive Thyroid), Myxedema Coma|
|Form:||Liquid solution, Intramuscular (IM), Intravenous (IV)|
|Ingredients:||Anhydrous levothyroxine sodium (levothyroxine), mannitol, sodium phosphate, dibasic heptahydrate, sodium hydroxide.|
About This Medication
What the Medication is Used For
Levothyroxine is a synthetic thyroid hormone used for treatment of hypothyroidism (low thyroid hormones secretion).
What it Does
The levothyroxine in Levothyroxine Sodium for Injection is intended to replace a hormone that is normally produced by your thyroid gland. Generally, replacement therapy is to be taken for life, except in cases of transient (temporary) hypothyroidism, which is usually associated with an inflammation of the thyroid gland (thyroiditis). Levothyroxine Sodium for Injection is used as a substitute for oral levothyroxine tablets when rapid treatment is required or when oral medication cannot be taken.
When it Should not be Used
Levothyroxine Sodium for Injection should not be used in patients with:
- overactive thyroid glands;
- uncorrected adrenal insufficiency (not enough adrenal hormones);
- acute myocardial infarction (heart attack);
- sensitivity to any of the inactive ingredients (see What the important nonmedicinal ingredients are).
What the Medicinal Ingredient Is
What the Important Nonmedicinal Ingredients Are
Mannitol, dibasic sodium phosphate heptahydrate, and sodium hydroxide
What Dosage Forms it Comes In
Levothyroxine Sodium for Injection is available as a sterile lyophilized powder for reconstitution. Your doctor has chosen the strength (dose) that he or she thinks will be most effective in relieving your condition, based on experience with similar medical problems.
Warnings and Precautions
Serious Warnings and Precautions
- Thyroid hormones, including levothyroxine, either alone or with other therapeutic agents, should not be used for the treatment of obesity or for weight loss.
- In patients with normal thyroid function, doses within the range of daily hormonal requirements are ineffective for weight reduction.
- Larger doses may produce serious or even life-threatening toxic effects, particularly when taken with products used for their appetite suppressing effects.
Tell your Doctor Before and While Using Levothyroxine Sodium for Injection
- if you are allergic to any foods or medicines;
- if you are taking any other prescription, non-prescription (over-the-counter) medications, or herbal/alternative supplements;
- if you have, either presently or in the past, any other medical problems, whether or not you have received treatment for them (especially hardening of the arteries, heart disease, high blood pressure, osteoporosis, blood clotting disorders, or history of thyroid, adrenal, or pituitary gland problems);
- if you have diabetes, your dose of insulin or oral antidiabetic agent may need to be changed after starting Levothyroxine Sodium for Injection. You should monitor your blood and urinary glucose levels as directed by your doctor and report any changes to your doctor immediately;
- if you are taking an oral anticoagulant drug (blood thinner) such as warfarin, your dose may need to be changed after starting Levothyroxine Sodium for Injection. Your coagulation status should be checked often to determine if a change in dose is required;
- if you are or intend to become pregnant, or are breast-feeding. Your dose of this medicine will likely have to be increased while you are pregnant.
You should inform your doctor or dentist that you are taking Levothyroxine Sodium for Injection before having any kind of surgery.
Interactions With This Medication
Drugs that may interact with Levothyroxine Sodium for Injection include but are not limited to the following:
- oral anticoagulants (blood thinners);
- digitalis glycosides (e.g., digoxin);
- antidiabetic agents (insulin or oral hypoglycemic drugs);
- beta-adrenergic antagonists (e.g., metoprolol, atenolol, bisoprolol, propranolol);
- glucocorticoids (corticosteroids, e.g., dexamethasone);
- diazepam (e.g., Valium);
- sympathomimetics [e.g., Ventolin (salbutamol)];
- propylthiouracil (PTU);
Levothyroxine Sodium for Injection can interfere with the actions of other medications. When you are taking Levothyroxine Sodium for Injection, it is important to let your doctor know if you are taking any other medications, including prescription medications, over-the-counter medications, vitamins and herbal products.
Proper Use of This Medication
Your doctor will decide and adjust your dosage depending upon your response to the medication. The starting dose of levothyroxine sodium, the frequency of dose titration, and the optimal full replacement dose must be individualized for every patient, and will be influenced by such factors as age, weight, cardiovascular status, presence of other illness, and the severity and duration of hypothyroid symptoms.
Side Effects and What to do About Them
Adverse reactions associated with Levothyroxine Sodium for Injection are primarily due to therapeutic overdosage. Tell your doctor/health professional immediately if you experience any of these symptoms, or if you experience any other unusual medical event:
- compromised adult height
- fatigue, sleeplessness
- change in appetite, weight gain or loss
- heat intolerance, fever, flushing
- excessive sweating
- hives or skin rash
- hyperactivity, nervousness, anxiety, irritability, emotional lability
- tremors, muscle weakness, abdominal and leg cramps
- chest pain, rapid or irregular heartbeat, increased blood pressure, heart failure, angina, myocardial infarction/cardiac arrest (heart attack), shortness of breath
- diarrhea, vomiting
- hair loss (may occur rarely during the first few months of Levothyroxine Sodium for Injection therapy, but it is usually temporary)
- menstrual irregularities, and impaired fertility.
Contact your doctor if results of tests show:
- elevations in liver function tests
- decreased bone mineral density.
This is not a complete list of side effects. For any unexpected effects while taking Levothyroxine Sodium for Injection, contact your doctor or pharmacist.
How to Store It
Store at room temperature (15 to 30˚C, 59 to 86˚F), protected from light.
KEEP LEVOTHYROXINE SODIUM FOR INJECTION OUT OF THE REACH OF CHILDREN.
Reporting Side Effects
You can help improve the safe use of health products for Canadians by reporting serious and unexpected side effects to Health Canada. Your report may help to identify new side effects and change the product safety information.
3 ways to report:
- Online at MedEffect (http://hc-sc.gc.ca/dhp-mps/medeff/index-eng.php);
- By calling 1-866-234-2345 (toll-free);
- By completing a Consumer Side Effect Reporting Form and sending it by:
- Fax to 1-866-678-6789 (toll-free), or
- Mail to: Canada Vigilance Program
Health Canada, Postal Locator 0701E
Postage paid labels and the Consumer Side Effect Reporting Form are available at MedEffect (http://hc-sc.gc.ca/dhp-mps/medeff/index-eng.php).
NOTE: Contact your health professional if you need information about how to manage your side effects. The Canada Vigilance Program does not provide medical advice.
This document plus the full product monograph, prepared for health professionals, can be obtained by contacting the sponsor, Fresenius Kabi Canada Ltd., at 1-877-821-7724.