Synthroid Uses, Dosage & Side Effects

Patients need to feel comfortable to alert me of any changes in their status in terms of their symptoms. But also specific medical changes that may indicate there may be a need for a dose change or something that could have affected their thyroid hormone levels. For adult patients with primary hypothyroidism, titrate until the patient is clinically euthyroid and the serum TSH returns to normal. If levothyroxine is ingested along with food, its absorption can be impaired 15, 51.

Endorsed Clinical Guidance

Please see the additional Important Safety Information at the end of this video, including the BOXED WARNING regarding inappropriate treatment for obesity or for weight loss. Primary hypothyroidism is basically diagnosed off of a screening TSH, or thyroid stimulating hormone. Administer SYNTHROID to pediatric patients who cannot swallow intact tablets by crushing the tablet, suspending the cheaper synthroid freshly crushed tablet in a small amount (5 to 10 mL) of water and immediately administering the suspension by spoon or dropper. Do not administer in foods that decrease absorption of SYNTHROID, such as soybean-based infant formula. In summary, it is necessary in all cases to periodically verify the need for dose adjustment and/or continuation of treatment.

Moreover, despite several randomized controlled trials showing a lack of benefit of combining triiodothyronine with levothyroxine in such patients,51 it is possible that triiodothyronine formulated to mimic the normal physiological profile may have a better outcome. Indeed, a proof of concept study has demonstrated the biochemical efficacy of a combination of long-acting triiodothyronine and levothyroxine on the T4/T3 ratio and TSH over levothyroxine monotherapy.101 Further studies are required to see whether this biochemical advantage translates into clinical benefit. Finally, recent genetic studies have shown associations between common genetic variations and thyroid hormone levels,23–26,55,102 wellbeing in levothyroxine- treated patients,55 and response to triiodothyronine-levothyroxine combination treatment,55 opening the door to the possibility of pharmacogenomics. Future genetic studies may help in identifying the subgroup of patients who would benefit from combination therapy. Prolonged untreated hypothyroidism can lead to persistent bradycardia, an adverse atherogenic lipid profile, and deterioration in myocardial function. Thyroid hormones, including SYNTHROID, either alone or with other therapeutic agents, should not be used for the treatment of obesity or for weight loss.

Factors Potentially Contributing to the Need for Levothyroxine Dose Adjustments Throughout a Patient’s Life Span

• In pregnant patients with primary hypothyroidism, maintain serum TSH in the trimester-specific reference range.
• Pituitary Thyrotropin (Thyroid Stimulating Hormone, TSH) SuppressionSYNTHROID is indicated in adult and pediatric patients, including neonates, as an adjunct to surgery and radioiodine therapy in the management of thyrotropin-dependent well-differentiated thyroid cancer.
• Patients with coronary artery disease who are receiving SYNTHROID should be closely monitored for cardiac arrhythmias during surgical procedures.
• Synthroid works best if you take it on an empty stomach, 30 to 60 minutes before breakfast.

In euthyroid patients, doses within the range of daily hormonal requirements are ineffective for weight reduction. Larger doses may produce serious or even life-threatening manifestations of toxicity, particularly when given in association with sympathomimetic amines such as those used for their anorectic effects. Hypothyroidism, a reduction in thyroid hormone levels, is one of the most common diseases worldwide. The medication most used to treat hypothyroidism is levothyroxine, a compound that acts as a replacement for a person’s thyroid hormone. People with hypothyroidism will often need to take levothyroxine for a long time, typically for the rest of their life, so it is important that their treatment is monitored closely and the dose is adjusted for the best effect as needed.

• However, you may not be able to take this medicine if you have certain medical conditions.
• Look to see if the tablets have Synthroid embossed on them to ensure they’re getting the right product.
• Because a high dose of levothyroxine may exacerbate angina or precipitate myocardial infarction, the weekly regime of levothyroxine is not appropriate for patients with ischemic heart disease.
• Optimal treatment of hypothyroidism requires a partnership between patient and physician.

When commencing levothyroxine therapy, initial dose requirements can vary greatly from small doses such as 25–50μg in an individual with mild or subclinical disease, where the therapy may be supplementing endogenous function, to larger doses of 88–175 μg in cases of patients with negligible endogenous thyroid function. In keeping with this concept, the initial dose of levothyroxine in patients presenting to a clinic with primary hypothyroidism can be predicted by the patient’s TSH value prior to initiation of treatment 9. In the case of surgically athyreotic patients, the dose of levothyroxine required may be slightly higher than in those with autoimmune thyroid disease 8, presumably reflecting some retained thyroid hormone production in those with autoimmune thyroid disease. An example of the dose requirement in those with Hashimoto’s thyroiditis without residual function and post-surgical hypothyroidism is approximately 1.6 μg/kg 8. The dose of levothyroxine required by a patient following thyroidectomy can be predicted by either body weight or body mass index (BMI) 10–12. Body weight, BMI, ideal body weight, and lean body mass can all predict the initial dose requirement, with the latter three parameters providing the more accurate estimates 10, 13.

• Unithroid is used for hashimoto’s disease, hypothyroidism, after thyroid removal, myxedema coma …
• As levothyroxine is usually administered over a patient’s lifetime, physiological changes throughout life will affect the dose of levothyroxine required to maintain euthyroidism.
• There is currently no other treatment for hypothyroidism, other than providing thyroid hormone replacement.
• Several medications, supplements, and food can interfere with the absorption and action of levothyroxine (Table 2).

Timing of levothyroxine

Oral selenium supplementation appears to have efficacy in modifying the natural history of Graves’ orbitopathy,100 and may prove to have immunomodulatory actions in other forms of autoimmune thyroid disease. In pregnancy, results of ongoing and future clinical trials are awaited to inform whether all pregnant women should be screened and treated for subclinical hypothyroidism. A significant minority of hypothyroid patients treated with levothyroxine do not feel completely well and have a poorer quality of life.11 There are several possible causes for impaired wellbeing in these patients.

SYNTHROID has been committed to treating hypothyroidism for 65 years.3

This is a key issue for some of the elemental things like calcium and iron, that can interfere with thyroid hormone absorption and thus should be taken approximately 4 hours apart. They can have changes in the female hormone status, either going on or off a birth control pill, going through menopause. Knowing that patient behaviors and consistency of treatment are key factors in treatment success, I educate patients on the process as they begin treatment. To minimize the risk of hyperactivity, start at one-fourth the recommended full replacement dosage, and increase on a weekly basis by one-fourth the full recommended replacement dosage until the full recommended replacement dosage is reached. ​Inquire whether patients are taking biotin or biotin-containing supplements.

Since thyroid hormone occurs naturally in the body, almost anyone can take levothyroxine. However, you may not be able to take this medicine if you have certain medical conditions. And to adjust the dose based on periodic assessment of the patient’s clinical response and their laboratory values. The second is that Synthroid has a history, as physicians have been treating patients with hypothyroidism with Synthroid for over 65 years.

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. Its chemical structure was determined in 1926 by Harington, and it was synthesised in 1927 by Harington and Barger 1, 2. The acidity of the thyroxine molecule, which caused diminished absorption resulting in low bioavailability, was an unresolved problem for more than 20 years following its discovery 3.

Assess compliance, dose of medication administered, and method of administration prior to increasing the dose of SYNTHROID. A recent survey, which queried the treatment of hypothyroidism by presenting 13 theoretical patients and offering 6 therapeutic options, was emailed to the members of the American Thyroid Association (ATA) prior to a satellite symposium of their Spring Meeting and also before the annual Endocrine Society and ATA Meetings. A multivariate analysis of the results revealed that physician characteristics may affect prescription patterns, with residents of North America, for example, being more inclined to prescribe therapies incorporating liothyronine than their colleagues in Europe 85, 86. However, the study was not designed to investigate whether this was due to physician-patient interaction, specific education following the meetings, the influence of pharmaceutical companies, or media exposure, or a combination of these.