Testosterone Pellets: What the Published Series and Labels Report

By Benn Bluestein-Veyra, M.Sc. Organic Chemistry · Updated 8 November 2026

The published evidence on testosterone pellets consists of one FDA-approved product label and a set of retrospective series, one open-label phase IV study and one small randomized trial. Testopel, approved in 1972 and relabeled most recently in July 2025, is the only prescription testosterone pellet Drugs@FDA lists as of 8 November 2026.^[1][2] Its label warns of implant site infection and pellet extrusion and states that pellet implantation "is much less flexible for dosage adjustment" than injections.^[1] The series report sustained testosterone concentrations for several months after implantation, extrusion and infection rates that varied with surgical technique, and hematocrit findings that ranged from a small mean rise in one cohort to erythrocytosis in about a third of men in others.^[3][4][5][6]

This page reports what each label, study and regulation states, attributed to its source, for licensed practitioners who evaluate an implanted hormone service. Testosterone is a Schedule III controlled substance, so storage, dispensing records and the place of registration all apply to pellets kept or inserted in a practice.^[7] The guideline thresholds for hematocrit and PSA are set out on the companion page on testosterone therapy guidelines and TRAVERSE, and the National Academies review of compounded hormones, including its pellet findings, has its own page in this cluster.

Drugs@FDA lists Testopel as the one approved testosterone pellet still marketed

Drugs@FDA records Testopel under ANDA 080911, an implantation pellet with a prescription marketing status, original approval on 13 July 1972 and a labeling supplement approved on 11 July 2025.^[2] An openFDA query of Drugs@FDA on 8 November 2026 for pellets given by implantation returned Testopel and a discontinued desoxycorticosterone product, and no estradiol pellet.^[2] A second testosterone pellet, Oreton, lost its approval on 23 September 2024 when FDA withdrew NDA 004652 because its holder had "repeatedly failed to file required annual reports".^[8]

The label, revised 07/2025 and published on DailyMed by Endo USA, describes cylindrical sterile pellets of crystalline testosterone with stearic acid and polyvinylpyrrolidone as inactive ingredients, which "slowly release the hormone for a long acting androgenic effect" when implanted subcutaneously.^[1] FDA's Testosterone Information page, current as of 23 June 2026, lists the approved formulations as "the topical gel, transdermal patch, buccal system (applied to upper gum or inner cheek), and injection" and does not mention pellets.^[9]

The Testopel label limits use to defined deficiency states and still carries the age-related limitation

The label states that androgens "are indicated for replacement therapy in conditions associated with a deficiency or absence of endogenous testosterone", naming primary hypogonadism and hypogonadotropic hypogonadism, and adds that "Safety and efficacy of TESTOPEL® (testosterone pellets) in men with “age-related hypogonadism” (also referred to as “late-onset hypogonadism”) have not been established."^[1] Before initiation it directs the prescriber to "confirm the diagnosis of hypogonadism by ensuring that serum testosterone concentrations have been measured in the morning on at least two separate days and that these serum testosterone concentrations are below the normal range."^[1]

FDA's page states that in June 2026 the agency requested updates to testosterone prescribing information that included "Removing the limitation of use stating the safety and efficacy of testosterone replacement therapy in men with age-related hypogonadism" and revising prostate safety information.^[9] As of 8 November 2026, the published Testopel label does not yet reflect that request: it retains the limitation, carries no boxed warning, and still contains the older paragraph stating that "Long term clinical safety trials have not been conducted to assess the cardiovascular outcomes of testosterone replacement therapy in men."^[1] Its warnings also include venous thromboembolism, a blood pressure warning stating that testosterone "can increase blood pressure which can increase cardiovascular (CV) risk over time", and a section on abuse and dependence.^[1]

The label warns that implant site infection and extrusion were reported mostly within the first month

The warnings section reads: "Post-marketing cases associate TESTOPEL® pellet(s) insertion with implant site infection (cellulitis and abscess), and/or pellet extrusion at or near the implantation site."^[1] The reported signs "included induration, inflammation, fibrosis, bleeding, bruising, wound drainage, pain, itching, and pellet extrusion", and the label states that "Although cases of infection and/or extrusion may occur at any time, most reported cases occurred within the first month after TESTOPEL® implantation."^[1]

Two precautions are specific to the dosage form. The label states that pellet implantation "is much less flexible for dosage adjustment than is oral administration of or intramuscular injections of oil solutions or aqueous suspensions", and that "In the face of complications where the effects of testosterone should be discontinued, the pellets would have to be removed."^[1] Its laboratory section states that "Hemoglobin and hematocrit should be checked periodically for polycythemia in patients who are receiving high doses of androgens."^[1]

The label and the early series describe release that falls over the months after implantation

On absorption, the label states that "approximately one-third of the material is absorbed in the first month, one-fourth in the second month and one-sixth in the third month", and that the effect ordinarily continues for several months.^[1] A six-institution retrospective analysis of 380 men undergoing 702 insertions reported that pellets raised total testosterone into the therapeutic range by one month and sustained concentrations above 300 ng/dL for four to six months; four extrusions and three hematomas were reported "early in our experience".^[3]

A Baylor College of Medicine review of 273 men and 501 insertions analyzed serum total testosterone, free testosterone and estradiol against time from implantation.^[10] Men with a body mass index of 25 or above reached lower testosterone peaks with slower decay, estradiol rose significantly only in men who received the larger pellet numbers, one man developed erythrocytosis, and the authors wrote that "Optimal dosing, frequency of reimplantation, and long-term safety of T pellets remain incompletely elucidated parameters."^[10] A single-center, open-label phase IV study reported that mean testosterone rose and luteinizing hormone fell at weeks 1, 4 and 12, that both had returned to pre-implantation levels by week 24, and that PSA was unchanged over the study.^[11]

Procedure series report extrusion and infection rates that varied with technique

A retrospective review of 168 men and 281 implantation procedures compared a single linear subcutaneous track with a modified technique using two angled tracks from one incision.^[4] Extrusion occurred in 7.5 percent of standard-technique procedures and 0.8 percent of modified-technique procedures, infection in 5 percent and 1.2 percent, and pain prompting discontinuation in 7.5 percent and 1.7 percent; hematoma occurred only with the modified technique, in 1.2 percent.^[4] None of the men with infection or bleeding required further surgery.^[4]

The largest series is a review of practitioner-reported data on 1,204,012 testosterone and estradiol implant procedures in 376,254 patients from 2012 to 2019, 85 percent of them in women.^[12] The author reported an overall complication rate below 1 percent, with extrusion the most common event, more frequent in men than in women; the paper discloses that the author founded the company whose tracking software collected the data.^[12] In a survey of 113 men at an academic urology clinic, convenience was the most common reason for starting pellets, cost was the main reason for stopping, and 28.3 percent had discontinued.^[13]

Hematocrit findings in pellet series range from a small mean rise to erythrocytosis in a third of men

A multi-institutional review of 97 men reported mean hematocrit of 43.9 percent before and 46.1 percent after implantation, an increase of 2.2 percentage points, and found that pretreatment hematocrit was inversely related to the change; the authors judged the increase "unlikely to translate into clinical relevance" for that cohort.^[5] A single-institution review of 228 men, defining polycythemia as hematocrit above 50 percent, estimated rates of 10.4 percent at 6 months, 17.3 percent at 12 months and 30.2 percent at 24 months, and concluded that the incidence "may be higher than previously established".^[6]

A three-year comparison of 178 men on a single formulation reported erythrocytosis, defined as hematocrit above 50 percent, in 66.7 percent of men on injections, 35.1 percent on pellets and 12.8 percent on gels, with no PSA increases in any group.^[14] In women, a retrospective chart review of 220 pellet insertions performed between 2009 and 2022 in women with low libido reported no significant change in hematocrit or systolic blood pressure; its authors disclose consulting relationships and the ownership of a for-profit practice.^[15] The monitoring thresholds that the Endocrine Society attaches to hematocrit during testosterone treatment are quoted on the guidelines and TRAVERSE page.

One randomized trial compared a compounded pellet with the approved product

A single-center, phase 3, randomized noninferiority trial assigned 75 men with testosterone deficiency to Testopel or to a compounded testosterone pellet and followed them at 2, 4 and 6 months with morning testosterone, estradiol, hematocrit and PSA.^[16] Serum testosterone was similar between groups at each visit, 82 percent of men had fallen below 300 ng/dL by the end of the trial, and adverse events, including rises in PSA, estradiol and hematocrit, were similar; the authors listed the single-institution cohort and limited external validity as limitations.^[16]

For compounded estradiol and testosterone pellets more broadly, the National Academies report recommended that FDA's Pharmacy Compounding Advisory Committee consider all compounded bioidentical hormone preparations in pellet form as candidates for the list of products that are demonstrably difficult to compound.^[17] The reasoning behind that recommendation, the medical-record study of women on pellets that the report and later authors discuss, and the status of FDA's difficult-to-compound rulemaking are covered on the NASEM 2020 page of this cluster.

Section 503A requires an identified patient, which decides how office pellet stock is sourced

Section 503A exempts a compounded drug from the approval requirement only "if the drug product is compounded for an identified individual patient based on the receipt of a valid prescription order", and it bars a 503A pharmacy from compounding "regularly or in inordinate amounts" any drug products "that are essentially copies of a commercially available drug product".^[18] A compounded testosterone pellet therefore reaches a patient through a prescription written for that patient, and the existence of an approved pellet brings the copies condition into play unless the prescriber documents a change that produces "a significant difference" for the patient.^[18]

Section 503B describes an outsourcing facility that "is engaged in the compounding of sterile drugs", has registered as such, and "may or may not obtain prescriptions for identified individual patients".^[19] A practice that wants pellets on hand before a patient is identified is therefore choosing between an approved product and an outsourcing facility; the comparison page on 503A and 503B office use, labels and CGMP sets out the two routes side by side.

Schedule III rules govern pellet storage, dispensing logs and each place of registration

Testosterone appears at 21 CFR 1308.13(f) as "(84) testosterone (17β-hydroxyandrost-4-en-3-one)", and the Testopel label states that the product "contains testosterone, a Schedule III controlled substance in the Controlled Substances Act."^[1][7] For practitioners, 21 CFR 1301.75(b) requires that Schedule II through V substances "be stored in a securely locked, substantially constructed cabinet".^[20] Under 21 CFR 1304.22(c), a registrant who dispenses must keep records of "the number of units or volume of such finished form dispensed, including the name and address of the person to whom it was dispensed, the date of dispensing, the number of units or volume dispensed, and the written or typewritten name or initials of the individual who dispensed or administered the substance".^[21]

Registration is tied to a place. Under 21 CFR 1301.12(a), "A separate registration is required for each principal place of business or professional practice at one general physical location where controlled substances are manufactured, distributed, imported, exported, or dispensed by a person."^[22] Read with the storage and record rules above, a practice that keeps pellets for insertion holds them in a locked cabinet at a registered location and logs each one dispensed or administered there.^[20][21][22]

Compounded hormone preparations reach a practice working with ExaVeyra through a licensed 503A pharmacy partner on a patient-specific prescription, and the partner dispenses testosterone and any other controlled substance under its own DEA registration.^[7][18] Whether a patient is a candidate for an implanted hormone, which product is prescribed, and how hematocrit, PSA and the implant site are monitored are decisions for the prescribing practitioner, documented against the label and guideline the practice follows.^[1][10]

This article summarizes published clinical practice guidelines, trial reports and federal regulation for licensed practitioner education. It is not legal advice, medical advice, or regulatory guidance, and it does not establish that any particular product or practice is compliant. Confirm current federal and state obligations with qualified counsel.