Thyroid Hormone Withdrawal (THW) May Cause Acute Hypothyroidism¹

Contraindications

If Thyrogen is administered with radioiodine, the contraindications to radioiodine also apply to this combination regimen. Refer to the radioiodine prescribing information for a list of contraindications for radioiodine.

Warnings and Precautions

Thyrogen-Induced Hyperthyroidism:

• There have been reports of death in non-thyroidectomized patients and in patients with distant metastatic thyroid cancer in which events leading to death occurred within 24 hours after administration of Thyrogen. Caution should be exercised in patients who have substantial thyroid tissue still in situ or functional thyroid cancer metastases, specifically in the elderly and those with a known history of heart disease.
• Hospitalization for administration of Thyrogen and post-administration observation in patients at risk should be considered.

Stroke:

• There are post marketing reports of stroke in young women with risk factors for stroke, and neurological findings suggestive of stroke (e.g., unilateral weakness) occurring within 72 hours of Thyrogen administration in patients without known central nervous system metastases. The relationship between Thyrogen administration and stroke is unknown. Patients should be well-hydrated prior to treatment with Thyrogen.

Sudden Rapid Tumor Enlargement: 

• Sudden, rapid and painful enlargement of residual thyroid tissue or distant metastases can occur following treatment with Thyrogen. Pretreatment with glucocorticoids should be considered for patients in whom tumor expansion may compromise vital anatomic structures.

Risks Associated with Radioiodine Treatment: 

• If Thyrogen is administered with radioiodine (RAI), the warnings and precautions for RAI apply to this combination regimen. Refer to the RAI prescribing information for a full list of the warnings and precautions for RAI.

Adverse Reactions

The most common adverse reactions reported in clinical trials were nausea and headache.

Use in Specific Populations

Pregnancy:

• If Thyrogen is administered with radioiodine, the combination regimen is contraindicated in pregnant women.
• Available data with Thyrogen use in pregnant women are insufficient to evaluate for a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes.

Lactation:

• The concomitant use of Thyrogen and radioiodine (RAI) is contraindicated in lactating women. If Thyrogen is administered with RAI for diagnostic use, discontinue breastfeeding after RAI administration because of the potential for serious adverse reactions from RAI in the breastfed infant.
• If Thyrogen is not administered with RAI, the developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for Thyrogen and any potential adverse effects on the breastfed child. There are no available data on the presence of thyrotropin alfa in human milk, the effects on the breastfed infant, or the effects on milk production.

Pediatric Use: Safety and effectiveness in pediatric patients have not been established.

Geriatric Use: Results from controlled trials do not indicate a difference in the safety and efficacy of Thyrogen between adult patients less than 65 years and those over 65 years of age.

Renal Impairment: Elimination of Thyrogen is significantly slower in dialysis-dependent end stage renal disease patients, resulting in prolonged elevation of TSH levels.