Synthroid Levothyroxine Sodium: Side Effects, Uses, Dosage, Interactions, Warnings
Addition of levothyroxine therapy in patients with diabetes mellitus may worsen glycemic control and result in increased antidiabetic agent or insulin requirements. Carefully monitor glycemic control after starting, changing, or discontinuing SYNTHROID see DRUG INTERACTIONS. Titrate the dose of SYNTHROID carefully and monitor response to titration to avoid these effects see DOSAGE AND ADMINISTRATION. Consider the potential for food or drug interactions and adjust the administration or dosage of SYNTHROID as needed see DOSAGE AND ADMINISTRATION, DRUG INTERACTIONS and CLINICAL PHARMACOLOGY.
SYNTHROID®(levothyroxine sodium tablets, USP)
Dosing must be individualized and adjustments made based on periodic assessment of the patient’s clinical response and laboratory parameters (see PRECAUTIONS – Laboratory Tests). In adult patients with primary (thyroidal) hypothyroidism, serum TSH levels (using a sensitive assay) alone may be used to monitor therapy. The frequency of TSH monitoring during levothyroxine dose titration depends on the clinical situation but it is generally recommended at 6-8 week intervals until normalization. For patients who have recently initiated levothyroxine therapy and whose synthroid cardiotoxic serum TSH has normalized or in patients who have had their dosage or brand of levothyroxine changed, the serum TSH concentration should be measured after 8-12 weeks. When the optimum replacement dose has been attained, clinical (physical examination) and biochemical monitoring may be performed every 6-12 months, depending on the clinical situation, and whenever there is a change in the patient’s status.
Studies in women taking levothyroxine sodium during pregnancy have not shown an increased risk of congenital abnormalities. SYNTHROID should not be discontinued during pregnancy and hypothyroidism diagnosed during pregnancy should be promptly treated. When you have hypothyroidism, the thyroid doesn’t produce, or can’t produce enough thyroid hormones. When your thyroid hormone level decreases, it results in your body’s system slowing down, including your metabolism, which may lead to symptoms such as sensitivity to cold, weight gain, and fatigue.
- Levothyroxine is the most commonly used treatment in this setting.
- The liver is the major site of degradation for both T4 and T3, with T4 deiodination also occurring at a number of additional sites, including the kidney and other tissues.
- SYNTHROID is contraindicated in patients with uncorrected adrenal insufficiency see WARNINGS AND PRECAUTIONS.
- Reduce the SYNTHROID dosage or discontinue temporarily if signs or symptoms of overdosage occur.
- In children in whom a diagnosis of permanent hypothyroidism has not been established, it is recommended that levothyroxine administration be discontinued for a 30-day trial period, but only after the child is at least 3 years of age.
Congenital Hypothyroidism
When serum T3 and T4 levels increase, TRH and TSH secretion decrease. When thyroid hormone levels decrease, TRH and TSH secretion increase. Because of the increased prevalence of cardiovascular disease among the elderly, initiate SYNTHROID at less than the full replacement dose see DOSAGE AND ADMINISTRATION and WARNINGS AND PRECAUTIONS.
Exercise caution when administering levothyroxine to patients with cardiovascular disorders and to the elderly in whom there is an increased risk of occult cardiac disease. In these patients, levothyroxine therapy should be initiated at lower doses than those recommended in younger individuals or in patients without cardiac disease (see WARNINGS, PRECAUTIONS – Geriatric Use, and DOSAGE AND ADMINISTRATION). If cardiac symptoms develop or worsen, the levothyroxine dose should be reduced or withheld for one week and then cautiously restarted at a lower dose.
Hypothyroidism
Enter medications to view a detailed interaction report using our Drug Interaction Checker. Do not share this medicine with another person, even if they have the same symptoms you have. Store at 25°C (77°F); excursions permitted to 15°-30°C (59°-86°F) see USP Controlled Room Temperature. Yuan et al. discovered that sesamol attenuates scopolamine-induced cholinergic disorders, neuroinflammation, and cognitive deficits in mice.
Treatment of Overdosage
And a third is those that have severe, long-standing hypothyroidism. Do not store the crushed tablet/water mixture and do not administer it mixed with foods that decrease absorption of levothyroxine, such as soybean-based infant formula. Pseudotumor cerebri and slipped capital femoral epiphysis have been reported in children receiving levothyroxine therapy.
Careful titration of medication and monitoring is required in that setting. Armour Thyroid is used for hashimoto’s disease, hypothyroidism, after thyroid removal, thyroid … Synthroid works best if you take it on an empty stomach, 30 to 60 minutes before breakfast.
The recommended daily dosage of SYNTHROID in pregnant patients is described in Table 3. The importance of writing “Dispense as Written,” or using the state-specific language for SYNTHROID, is something I discuss with my staff as well. Levothyroxine is one of the ten NTI drug classes most commonly prescribed. These medications are those where small changes in the dose or blood concentration may lead to serious therapeutic failures and/or adverse drug reactions.
Metabolism
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. Undertreatment and overtreatment should be avoided (see PRECAUTIONS – Pediatric Use). SYNTHROID may be administered to infants and children who cannot swallow intact tablets by crushing the tablet and suspending the freshly crushed tablet in a small amount (5-10 mL or 1-2 teaspoons) of water. Foods that decrease absorption of levothyroxine, such as soybean infant formula, should not be used for administering levothyroxine sodium tablets (see PRECAUTIONS – Drug-Food Interactions). In general, levothyroxine therapy should be instituted at full replacement doses as soon as possible. Delays in diagnosis and institution of therapy may have deleterious effects on the child’s intellectual and physical growth and development.