Thyrotropin alpha is a synthetic Thyrotropin-releasing hormone (TRH). TRH is a hormone secreted by the pituitary gland that stimulates the synthesis and release of thyroid hormone. In the treatment of thyroid cancer, Thyrotropin alpha is often used before thyroidectomy and before radioactive iodine treatment to increase the sensitivity of radioactive iodine scanning. Before surgery, Thyrotropin alpha simulates the effects of thyroid stimulating hormone, making the residual area of thyroid cancer easier to scan. This helps to assess the condition of thyroid cancer and locate the treatment area. So, what is the specific usage and dosage of Thyrotropin alpha?

Dosage and Administration of TSH α

1. Recommended Dosage

(1) Physicians familiar with the management of patients with thyroid cancer should use TSH α

(2) TSH α is suitable for a two-injection regimen. The recommended dose of TSH α is 0.9 mg intramuscular injection into the buttocks, followed by a second intramuscular injection into the buttocks 24 hours later, at a dose of 0.9 mg

(3) TSH α can only be injected intramuscularly and should not be injected intravenously

(4) For patients whose tumor expansion may endanger important anatomical structures, pretreatment with glucocorticoids should be considered

(5) Routine measurement of serum TSH levels is not recommended after the use of TSH α

2. Reconstitution, Preparation, and Administration of TSH α

The lyophilized powder provided must be reconstituted with sterile water for injection (United States Pharmacopoeia). TSH α should be prepared and administered in the following manner:

( 1) Reconstitute each vial of 0.9 mg of thyroxine with 1.2 ml of Sterile Water for Injection (USP) to obtain a single-dose solution containing 0.9 mg/ml Thyrotropin alfa, providing 1 ml (0.9 mg)

(2) Gently swirl the contents of the vial until all the material is dissolved. Do not shake the solution

(3) Before administration, visually inspect the reconstituted solution for particulate matter and discoloration. The reconstituted Thyrotropin alfa solution should be clear and colorless. Do not use if the solution contains particulate matter or is turbid or discolored

(4) Draw 1 ml of the reconstituted thyroxine solution (0.9 mg Thyrotropin alfa) and inject into the buttocks muscle. Discard any unused portion

(5) Unless refrigerated, the reconstituted thyroxine solution must be injected within 3 hours

(6) If necessary, the reconstituted solution can be stored refrigerated at 2°C-8°C for up to 24 hours hours, while avoiding microbial contamination

(7) Do not mix with other substances

3. Timing of serum thyroglobulin detection after Thyrotropin α administration

For serum thyroglobulin detection, serum samples should be collected 72 hours after the last injection of thyroxine

4. Timing of residual ablation and diagnostic scan after Thyrotropin α administration

For residual ablation and diagnostic scan, radioactive iodine should be taken orally 24 hours after the second injection of thyroxine, and the activity of 131I should be carefully selected by the nuclear medicine physician; diagnostic scan should be performed 48 hours after radioactive iodine administration.