Dehydroepiandrosterone sulfate (DHEA-S) is an endogenous steroid hormone primarily produced by the adrenal glands, with minor contributions from the gonads and brain. It belongs to the class of adrenal hormones and is a sulfated form of dehydroepiandrosterone (DHEA), which is a precursor to androgens and estrogens. DHEA-S is one of the most abundant circulating steroids in humans and serves as a reservoir that can be converted into more active steroid hormones. Researchers have found that DHEA-S plays a role in various physiological processes, including immune function, metabolism, and the development of secondary sexual characteristics. It is also a subject of interest in research areas such as aging, cardiovascular health, and neuroprotection. The mechanism of action of DHEA-S involves its conversion to DHEA, which then interacts with androgen and estrogen receptors, influencing a wide range of biological pathways. Researchers have observed that these pathways can affect cellular proliferation, differentiation, and apoptosis. DHEA-S itself does not directly bind to these receptors but serves as a precursor. Pharmacokinetically, DHEA-S has a relatively long circulating half-life of approximately 7 to 10 hours, allowing it to maintain stable levels in the bloodstream. It is metabolized primarily in the liver and excreted in urine. Oral bioavailability is limited due to first-pass metabolism. Clinically, DHEA-S levels are measured to assess adrenal function and diagnose disorders such as adrenal insufficiency or hyperplasia. It is not approved as a therapeutic agent in many countries, and its use is primarily limited to research settings. Regulatory standing varies, with some regions allowing over-the-counter sales of DHEA supplements, which can affect DHEA-S levels indirectly.