Online Synthroid (Levothyroxine)
Endocrine • Educational only; not medical advice. Prescriptions at clinician discretion.
Overview
Levothyroxine, marketed as Synthroid, is a synthetic form of thyroxine (T₄), the primary hormone produced by the thyroid gland. It replaces or supplements endogenous thyroid hormone in patients with hypothyroidism. Synthroid restores metabolic balance, supporting normal energy utilization, growth, and protein synthesis. It is one of the most prescribed chronic medications worldwide.
Uses
Indicated for primary, secondary, and tertiary hypothyroidism, thyroid cancer suppression, and post-thyroidectomy hormone replacement. It is also used diagnostically in suppression testing.Dosage & Administration
Individualized dosing based on serum TSH and free T₄ levels. Typical starting dose: 25–50 µg daily, titrated every 6–8 weeks. Take once daily on an empty stomach, ideally 30–60 minutes before breakfast with water. Avoid taking with calcium, iron, or soy products within 4 hours.Side Effects & Warnings
When properly dosed, adverse effects are minimal. Overdosage mimics hyperthyroidism: palpitations, tremor, insomnia, and weight loss. Long-term excessive doses can cause bone loss and arrhythmias. Contraindicated in untreated adrenal insufficiency or acute myocardial infarction.Patient Considerations
Adherence and timing consistency are crucial. Regular blood tests ensure correct dosage. Avoid switching brands without physician approval, as potency may vary.Ready for next steps?
Frequently asked questions
How long does Synthroid take to work?
Noticeable improvement in energy occurs within 2–3 weeks; full normalization takes up to 2 months.
Can I drink coffee after taking Synthroid?
Wait at least 30 minutes to prevent reduced absorption.
Is Synthroid safe in pregnancy?
Yes, maintaining normal thyroid levels is vital for fetal development; dose often increases.
Government / NIH sources
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