What is the Origin of Steady-State Delivery?

This concept originates in pharmacokinetics, describing the equilibrium reached when the rate of drug input equals the rate of drug output, a fundamental concept for chronic disease management. In hormonal wellness, it is the desired state when using continuous infusion pumps or long-acting depot injections.

What is the Mechanism of Steady-State Delivery?

When the dosing interval is short relative to the drug's half-life, the concentration gradually increases until the input and output rates equalize, establishing the steady state. For example, transdermal hormone patches are designed to provide near-zero-order absorption, mimicking the continuous pulsatile release characteristic of the healthy endocrine gland. This mechanism avoids supra-physiological spikes that can trigger negative feedback or cause receptor downregulation.

Steady-State Delivery

Meaning

Steady-State Delivery refers to the pharmacokinetic principle where a therapeutic agent, often a hormone or replacement compound, is administered at a rate that precisely matches its elimination rate from the body. Achieving this steady state results in consistent, stable plasma concentrations of the therapeutic agent, minimizing the peaks and troughs associated with intermittent dosing. This is crucial for managing conditions requiring continuous hormonal support, such as replacement therapy for hypothyroidism or hypogonadism.