What is the Origin of Subcutaneous Pellet Implantation?

The technique of implanting hormone pellets originated in the 1930s as an early method of delivering sustained hormone therapy, predating many modern transdermal and injectable formulations. The term 'subcutaneous' specifies the anatomical location, meaning 'beneath the skin,' and 'pellet' describes the solid, compressed form of the hormone preparation. It represents a long-established, albeit specialized, approach within clinical endocrinology.

What is the Mechanism of Subcutaneous Pellet Implantation?

The mechanism of delivery is diffusion-controlled, relying on the dissolution of the compressed hormone matrix into the surrounding interstitial fluid at a near-constant rate. The hormone then enters the capillary circulation and is transported systemically to target tissues. The rate of release is influenced by the pellet's surface area, density, and the patient's local blood flow, creating a steady-state serum concentration that closely mimics the body's natural, continuous endocrine secretion.

Subcutaneous Pellet Implantation ∞ Area

Subcutaneous Pellet Implantation

Meaning

Subcutaneous Pellet Implantation is a method of long-acting hormone delivery involving the sterile placement of small, compounded hormone pellets, typically containing bio-identical testosterone or estradiol, into the fatty tissue beneath the skin. This procedure is designed to provide a steady, continuous release of the hormone directly into the bloodstream over several months, thereby avoiding the peaks and troughs associated with daily oral or transdermal administration. It offers a convenient and physiologically consistent form of hormone replacement therapy.