Brand and Generic Medication Explained American Thyroid Association
Closely monitor infants during the first 2 weeks of SYNTHROID therapy for cardiac overload and arrhythmias. Long-term carcinogenicity studies in animals to evaluate the carcinogenic potential of levothyroxine have not been performed. Studies to evaluate mutagenic potential and animal fertility have not been performed. The recommended daily dosage of SYNTHROID in pregnant patients is described in Table 3. Our Synthroid Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.
But that difference could add up to the equivalent of anywhere from about half a pill less to an entire pill more than your intended dosage over the course of a week—even if you take your usual dosage as prescribed. Given that the FDA allows such a variation, it’s easy to think that it won’t make much difference which type you take. But levothyroxine has a “narrow therapeutic window,” meaning that treatment must be fine-tuned to achieve the desired effects. The Food and Drug Administration (FDA) has also approved the use of generic levothyroxine, which is made by several different pharmaceutical companies.
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And this isn’t the only study to show a difference between these medications. But despite both of these medications having the exact same ACTIVE ingredient (thyroxine) (1), they are not the EXACT same. Generic medications are usually created after a brand-name medication goes off-patent. The answer is yes, there may actually be a difference despite these medications being almost exactly the same. You may be more likely to have a broken bone while using levothyroxine.
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However, you may not be able to take this medicine if you have certain medical conditions. Converting hypothyroidism to the euthyroid state with levothyroxine may increase the blood level of theophylline (Slo-Bid), and it may be necessary to change the dose of theophylline. Therefore, a decrease synthroid gastritis in the dose of anticoagulant may be warranted with correction of the hypothyroid state or when the SYNTHROID dose is increased. Closely monitor coagulation tests to permit appropriate and timely dosage adjustments. For adult patients with primary hypothyroidism, titrate until the patient is clinically euthyroid and the serum TSH returns to normal see Recommended Dosage And Titration.
Concurrent use of sympathomimetics and SYNTHROID may increase the effects of sympathomimetics or thyroid hormone. Thyroid hormones may increase the risk of coronary insufficiency when sympathomimetic agents are administered to patients with coronary artery disease. Toxic effects may include increased risk of cardiac arrhythmias and central nervous system stimulation.
Questions to ask also include how well the medication works, how well patients do on the medication, and any safety issues. Generally, generic medications are less expensive than brand medications and are favored by most insurance companies. Insurance companies often require a trial of generic medicine before a brand medication is approved. Take levothyroxine tablets and capsules on an empty stomach, at least 30 to 60 minutes before breakfast with a full glass of water. You may not be able to use levothyroxine if you have certain medical conditions. Tell your doctor if you have an untreated or uncontrolled adrenal gland disorder or any heart problems such as a recent heart attack.
- And even though the difference is not big, it may actually matter to certain people (especially those who are sensitive).
- While the active ingredient is the same, the inactive ingredients added to improve absorption, preserve the drug, or add color can differ.
- Children can take the medicine if the tablet is crushed and put into about 1 to 2 teaspoons of water; do not store or delay giving this crushed pill suspension.
- Not all of the concerns about generic levothyroxine have been allayed.
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The generic levothyroxine product may contain the brand name as part of the labeling, so be sure to inspect your tablets when you receive a refill. Levothyroxine (Synthroid, Levoxyl, Levothroid, Unithroid, Tirosint, Levo-T) is a synthetic version of the principle thyroid hormone, thyroxine (T4), which is made and released by the thyroid gland. Thyroid hormone increases the metabolic rate of cells of all tissues in the body. It is prescribed to treat hypothyroidism and to suppress thyroid hormone release in the management of cancerous thyroid nodules and growth of goiters. It is important to be aware of drug interactions, as well as common side effects on the user. Published studies report that levothyroxine is present in human milk following the administration of oral levothyroxine.
Do not share this medicine with another person, even if they have the same symptoms you have. Synthroid works best if you take it on an empty stomach, 30 to 60 minutes before breakfast. Follow your doctor’s dosing instructions and try to take the medicine at the same time each day.
Thyroid disease often requires lifelong therapy and is best managed with consistent and precise treatment with the same brand of thyroid hormone. Your doctor may change your dose of thyroid hormone, but the brand of your thyroid hormone medication should be constant. Intravenous administration of epinephrine to patients with coronary artery disease may lead to complications ranging from difficulty in breathing to a heart attack.
For patients at risk of atrial fibrillation or patients with underlying cardiac disease, start with a lower dosage and titrate the dosage more slowly to avoid exacerbation of cardiac symptoms. Dosage titration is based on serum TSH or free-T4 see Important Considerations For Dosing. Thyroid hormones, including SYNTHROID, either alone or with other therapeutic agents, should not be used for the treatment of obesity or for weight loss.
