Levothyroxine Sodium Tablets (Euthyrox) are core medications for the treatment of hypothyroidism and the suppressive therapy after thyroid cancer surgery. Their efficacy is closely related to the standardization of medication use.
Precautions for Taking Levothyroxine Sodium Tablets (Euthyrox)
Administration Timing and Dietary Contraindications
Take on an empty stomach: It is recommended to take the medication at a fixed time every day, preferably 30-60 minutes before breakfast on an empty stomach, to maximize drug absorption rate.
Avoid substances that interfere with absorption: Calcium-containing and iron-containing drugs (such as calcium tablets, iron supplements), aluminum-magnesium antacids, and soy products.
High-fiber foods: Must be taken at least 4 hours apart from Euthyrox.
Grapefruit juice: May delay drug absorption and should not be taken together with Euthyrox.
Principles of Dose Adjustment
Individualized medication: The dose needs to be adjusted based on age, body weight, cardiovascular status, and pregnancy status.
Special populations:
Pregnant women have increased demand for thyroid hormones; regular TSH monitoring and dose adjustment are required.
Pediatric doses are calculated based on body weight; caution is needed against advanced bone age caused by over-treatment.
Contraindications and High-Risk Situations
Absolute contraindications: Contraindicated in patients with untreated adrenal insufficiency, as it may induce adrenal crisis.
Precautions for use:
Diabetic patients should note that Euthyrox may increase blood glucose; enhanced blood glucose monitoring is required.
Patients with osteoporosis should avoid long-term excessive medication.
Drug Interactions
Drugs affecting absorption: Proton pump inhibitors and bile acid sequestrants (such as cholestyramine) may reduce the efficacy of Euthyrox and need to be taken at intervals.
Drugs enhancing or weakening efficacy: When antidepressants and anticoagulants (such as warfarin) are used in combination with Euthyrox, close monitoring of relevant indicators is required.
Medication Monitoring for Levothyroxine Sodium Tablets (Euthyrox)
Thyroid Function Testing
Primary hypothyroidism: Serum TSH level is the main indicator. Testing is performed every 6-8 weeks in the early stage of treatment, and re-examination is conducted every 6-12 months after the condition stabilizes.
Secondary/tertiary hypothyroidism: Free T4 (FT4) needs to be monitored, with the target value being the upper-middle range of the normal range.
Pediatric patients: In addition to TSH and T4, regular assessment of growth and development, bone age, and neurological development is required.
Adverse Reaction Monitoring
Symptoms of overdose: Hyperthyroid manifestations such as palpitations, hand tremors, insomnia, and weight loss indicate the need for dose reduction. Elderly patients need to be alert to the risk of atrial fibrillation.
Long-term medication: Regular bone mineral density testing (especially for postmenopausal women) is required to avoid osteoporosis caused by over-treatment.
Monitoring for Special Populations
Pregnancy period: TSH is tested every 4 weeks; TSH should be maintained below 2.5 mIU/L in the first trimester and below 3.0 mIU/L in the second and third trimesters. The dose needs to be adjusted back to the pre-pregnancy dose in a timely manner after delivery.
Thyroid cancer patients: TSH suppression targets are formulated based on the risk of tumor recurrence, and a balance between cardiovascular and bone side effects is required.
