What is the primary active ingredient in Desicated Thyroid (Armour Thyroid)?

Desiccated thyroid, also known as Armour Thyroid, primarily contains pork-derived hormones, specifically a combination of T3 (liothyronine) and T4 (levothyroxine) that are extracted from the thyroid glands of pigs. This formulation aims to provide a more natural and whole gland approach to thyroid hormone replacement therapy, incorporating both hormones that the human body produces with the intent of mimicking natural thyroid function more closely than synthetic alternatives.

In contrast, levothyroxine and liothyronine are synthetic forms of the thyroid hormones T4 and T3, respectively, and are not the active ingredients in desiccated thyroid. Thyroid-stimulating hormone (TSH) is produced by the pituitary gland and plays a role in regulating thyroid hormone production, but is not present in desiccated thyroid preparations. This understanding underscores the significance of desiccated thyroid's source and formulation in treating hypothyroidism, providing insights into how it can differ from synthetic medications.