Medical spas glossary

Short, plain-English definitions of the terms you'll meet when choosing a medical spa provider in Florida TRT Clinics.

What are testosterone pellets (subcutaneous implants)?: Testosterone pellets are small solid implants inserted under the skin that release testosterone gradually over 3-6 months, providing consistent hormone levels without repeated injections or daily application.
What is a selective estrogen receptor modulator (SERM)?: A selective estrogen receptor modulator (SERM) is a drug that blocks estrogen receptors in specific tissues, used in testosterone therapy to stimulate the body's own testosterone production rather than replacing it externally.
What is an aromatase inhibitor?: Aromatase inhibitors are medications that block the enzyme aromatase, preventing the conversion of testosterone to estrogen in the body, commonly used as an ancillary treatment during testosterone replacement therapy.
What is anastrozole?: Anastrozole is an aromatase inhibitor medication that reduces estradiol conversion in men undergoing testosterone replacement therapy to prevent estrogen-related side effects.
What is aromatization?: Aromatization is the biological process by which the aromatase enzyme converts testosterone into estradiol, a form of estrogen. In men on TRT, managing aromatization is important to prevent excessive estrogen levels.
What is bioavailable testosterone?: Bioavailable testosterone is the fraction of total testosterone that is either free or loosely bound to albumin, capable of entering cells; it is calculated from total testosterone, SHBG, and albumin levels to assess functional hormone availability.
What is clomiphene (Clomid) therapy?: Clomiphene is an oral selective estrogen receptor modulator (SERM) that stimulates the pituitary gland to increase the body's natural testosterone production as an alternative to direct testosterone replacement.
What is estradiol (E2) in men?: Estradiol (E2) is the most potent estrogen in the male body and the primary form monitored during TRT, produced when the enzyme aromatase converts testosterone into estrogen.
What is free testosterone?: Free testosterone is the small portion of testosterone in the blood that is not bound to proteins and is therefore available for cells to use.
What is FSH (follicle stimulating hormone)?: FSH is a pituitary hormone that signals the testes to produce sperm and is measured in men undergoing testosterone replacement therapy to evaluate fertility and testicular function.
What is gonadorelin?: Gonadorelin is a gonadotropin-releasing hormone (GnRH) analog that stimulates the pituitary gland to maintain natural testosterone production and testicular function during TRT.
What is human chorionic gonadotropin (hCG)?: Human chorionic gonadotropin (hCG) is a hormone that mimics luteinizing hormone (LH) to stimulate the testes to produce testosterone and sperm, commonly used during testosterone replacement therapy to maintain fertility and testicular size.
What is hypogonadism?: Hypogonadism is a condition in which the body produces abnormally low levels of testosterone, stemming from either testicular failure (primary) or dysfunction in the pituitary gland or hypothalamus (secondary).
What is intramuscular vs subcutaneous injection?: Intramuscular injection (IM) delivers medication into muscle tissue using a longer needle, while subcutaneous injection (SC) deposits it in the fat layer beneath the skin with a shorter needle. Both are used for testosterone replacement therapy with different absorption rates and administration schedules.
What is LH (luteinizing hormone)?: Luteinizing hormone (LH) is a pituitary hormone that signals the testes to produce testosterone, and its level helps distinguish between central (pituitary) and primary (testicular) hypogonadism.
What is post-cycle therapy (PCT)?: Post-cycle therapy (PCT) is a pharmacological protocol administered after cessation of anabolic steroids or TRT to stimulate the body's natural testosterone production and restore hormonal balance.
What is primary vs secondary hypogonadism?: Primary hypogonadism originates in the testes and shows elevated LH and FSH; secondary hypogonadism originates in the pituitary or hypothalamus and shows low LH and FSH.
What is SHBG (sex hormone binding globulin)?: SHBG is a protein produced by the liver that binds to testosterone and estrogen in the bloodstream, determining how much of these hormones remain free and biologically active.
What is testicular atrophy?: Testicular atrophy is a reduction in testicle size that occurs during testosterone replacement therapy due to suppressed production of luteinizing hormone (LH) and follicle-stimulating hormone (FSH).
What is testosterone cypionate?: Testosterone cypionate is a long-acting synthetic testosterone ester administered via intramuscular injection, typically once weekly or every two weeks in testosterone replacement therapy.
What is testosterone enanthate?: Testosterone enanthate is a long-acting injectable form of testosterone attached to an enanthate ester, commonly used in TRT with a half-life of approximately 8-10 days and typical dosing intervals of every 7-10 days.
What is the hypothalamic-pituitary-gonadal (HPG) axis?: The HPG axis is a feedback loop between the brain and testes that regulates testosterone production; TRT suppresses this axis by reducing signals that normally trigger natural testosterone synthesis.
What is total testosterone?: Total testosterone is a blood lab measurement that quantifies all testosterone in circulation, including the portion bound to proteins and the unbound (free) fraction.
What is transdermal testosterone gel?: Transdermal testosterone gel is a topical formulation (such as AndroGel) applied directly to skin daily to deliver testosterone into the bloodstream through dermal absorption.