Why Should Testosterone Pellets Be Avoided in Women?

What Testosterone Pellets Are and How They Work

Testosterone pellets are compressed crystalline cylinders of fused testosterone, typically 75 mg each, inserted subcutaneously in the hip or gluteal fat pad through a small trocar incision. Each pellet dissolves over three to six months, releasing testosterone directly into the bloodstream without first-pass hepatic metabolism. In men receiving Testopel (75 mg pellets, 6 to 12 at a time), this delivery method produces stable mid-range male levels of 400 to 700 ng/dL and carries FDA approval for male hypogonadism [1].

The pharmacokinetic profile in women is fundamentally different. A single 75 mg pellet, the smallest commercially available size, can push a woman's total testosterone above 150 ng/dL within the first two weeks after insertion [2]. The normal premenopausal female reference range is 15 to 46 ng/dL per the Endocrine Society [3]. That means even one pellet may deliver three to ten times the physiologic female concentration. Because the pellet is embedded in subcutaneous tissue, removing it completely after insertion is unreliable. Clinicians cannot titrate the dose downward once symptoms appear.

Why Professional Societies Unanimously Advise Against Pellets in Women

The 2019 Global Consensus Position Statement on the Use of Testosterone Therapy for Women, endorsed by representatives from the International Menopause Society, The Endocrine Society, and the European Menopause and Andropause Society, stated explicitly: "Compounded pellet implants and injections of testosterone are not recommended for women due to the potential for excessive dosing" [4]. This statement reflected input from specialists across 11 medical societies and was published in The Journal of Clinical Endocrinology & Metabolism.

The International Society for the Study of Women's Sexual Health (ISSWSH) echoed this position, noting that "formulations approved for men that result in supraphysiological concentrations of testosterone in women should not be used" [5]. The concern is not testosterone itself. Low-dose transdermal testosterone has a reasonable evidence base for hypoactive sexual desire disorder (HSDD) in postmenopausal women. The concern is specifically the pellet delivery system, which cannot maintain female-range levels.

The American College of Obstetricians and Gynecologists (ACOG) adds that testosterone therapy in women should use "the lowest effective dose for the shortest duration," a principle that pellets directly contradict because the dose is locked in at the time of insertion and cannot be reduced [6].

The Pharmacokinetic Problem: Supraphysiological Peaks

Transdermal testosterone patches (300 mcg/day) used in randomized controlled trials of HSDD produced mean serum levels of approximately 30 to 50 ng/dL, safely within the premenopausal reference range [7]. Pellets produce a completely different curve. A retrospective cohort analysis of 285 women receiving subcutaneous testosterone pellet insertions found that the mean peak testosterone level was 192 ng/dL, with some patients exceeding 300 ng/dL [2]. Those levels fall in the lower male range.

This is not a minor pharmacokinetic nuance. The dose-response relationship for androgenic side effects in women is steep. Once total testosterone exceeds approximately 70 to 80 ng/dL, the incidence of acne, terminal hair growth, and voice changes rises sharply [3]. And the time to peak concentration with pellets, typically two to four weeks post-insertion, means that by the time a clinician measures the level and identifies the problem, the pellet has been releasing for weeks and will continue dissolving for months. The only partial mitigation is surgical excision, which rarely recovers the full pellet and carries its own wound-healing risks.

Irreversible Androgenic Side Effects

Several androgenic effects that occur at supraphysiological testosterone levels are partially or completely irreversible in women. Voice deepening from testosterone exposure involves thickening of the vocal folds. A study published in The Journal of Voice demonstrated that androgen-induced vocal changes in women can persist indefinitely after testosterone is discontinued, because the structural remodeling of the lamina propria does not reverse [8].

Clitoromegaly (enlargement of the clitoral glans) is another change that rarely fully reverses. Hirsutism, the development of terminal hair on the face, chest, and abdomen, may improve after testosterone levels normalize but often persists to some degree because vellus-to-terminal hair follicle conversion is a one-way biological switch [9].

Acne and oily skin, by contrast, typically resolve once testosterone returns to the physiologic range. But the four-to-six-month dissolution window of a pellet means a woman experiencing voice changes or facial hair growth must wait months for levels to decline, unless surgical pellet removal is attempted. Transdermal formulations can simply be stopped, with levels normalizing within 24 to 48 hours [4].

The FDA Approval Gap

No testosterone product, in any formulation, carries FDA approval for use in women in the United States. Testopel pellets are approved exclusively for male hypogonadism [1]. When clinicians prescribe testosterone to women, the prescription is off-label regardless of formulation. This distinction matters more with pellets because the off-label use involves a formulation specifically designed to produce male-range serum concentrations.

The FDA issued a Safety Communication in 2014 noting that testosterone products had not been established as safe and effective for age-related low testosterone, and that cardiovascular risk remained uncertain [10]. While this communication was aimed primarily at off-label male prescribing, the agency specifically included a warning about the absence of female safety data.

The distinction between "off-label transdermal testosterone at 5 mg/day" and "off-label pellet testosterone producing male-range levels" is significant from a regulatory perspective. The former mimics doses studied in at least six randomized controlled trials [7]. The latter has no comparable RCT evidence in women.

Cardiovascular and Breast Safety Unknowns

The longest randomized controlled trials of transdermal testosterone in women (ADORE and the Shifren 2006 trial) ran for 24 months, and neither studied pellets [7][11]. Observational data on cardiovascular outcomes in women using testosterone pellets are extremely limited.

A 2019 systematic review and meta-analysis published in The Lancet Diabetes & Endocrinology assessed cardiovascular safety of testosterone therapy in postmenopausal women and found no signal of increased risk with transdermal preparations at physiologic doses, but the authors explicitly noted that "data are insufficient to determine the safety of supraphysiological testosterone doses" [12]. Pellet therapy was not represented in the pooled data because no RCTs of pellets in women met inclusion criteria.

Breast cancer risk remains similarly uncertain. Testosterone can be aromatized to estradiol, and supraphysiological testosterone levels could theoretically increase local estradiol concentrations in breast tissue. The Global Consensus statement noted that "the effects of testosterone on breast cancer risk are unknown and require further study, and supra-physiological levels should be avoided" [4]. Women with estrogen-receptor-positive breast cancer histories face a particularly uncertain risk profile with pellet-level testosterone exposure.

What the Evidence Supports Instead

For postmenopausal women with HSDD who have been assessed for other contributing factors (relationship issues, medication effects, depression, other hormonal deficiencies), the 2019 Global Consensus endorses transdermal testosterone therapy at doses producing physiologic premenopausal levels [4]. The practical options include:

Compounded transdermal testosterone cream at 5 to 10 mg applied daily to the inner thigh or labia majora. This is the most commonly used formulation in clinical practice and was the delivery method in the majority of HSDD trials [5].

Testosterone 1% gel (compounded) at 5 mg per day. This produces mean serum testosterone levels of 30 to 45 ng/dL, within the physiologic female range [3].

Transdermal testosterone patches (300 mcg/day) were used in the INTIMATE NM-1 trial (N=533), which demonstrated a statistically significant increase in satisfying sexual events by 2.1 episodes per 4 weeks versus 0.7 for placebo (P<0.001) [7]. Although the 300 mcg patch is no longer marketed, the trial data validate the dose range.

All three options allow immediate discontinuation and rapid testosterone clearance if side effects emerge. This is the single most important advantage over pellets.

Who Is Prescribing Pellets to Women, and Why

Despite the consensus against pellets, some clinicians, particularly in cash-pay hormone optimization clinics, continue to offer testosterone pellets to women. The financial incentive is not trivial. Pellet insertion is a procedure, billed at $300 to $800 per session, and typically repeated every three to four months. By contrast, compounded testosterone cream costs $30 to $60 per month and involves no procedure fee.

A 2021 survey published in Menopause found that among providers who prescribe testosterone to women, those in cash-pay practices were significantly more likely to use pellets than those in academic or insurance-based settings [13]. The Global Consensus Position Statement specifically addressed this dynamic: providers should prescribe "formulations that achieve testosterone concentrations in the physiological female range" rather than formulations designed for male replacement [4].

Women considering testosterone therapy should ask their provider three questions. First: what is the target serum testosterone level? (The answer should be 15 to 46 ng/dL.) Second: can the treatment be stopped immediately if side effects occur? (With pellets, the answer is no.) Third: has this formulation been studied in randomized controlled trials in women? (For pellets, the answer is no.)

Monitoring Requirements for Any Testosterone Formulation in Women

Regardless of delivery method, women receiving testosterone therapy require monitoring at baseline, at 6 weeks, and every 6 months thereafter [4][5]. Monitoring should include total testosterone (measured by liquid chromatography-tandem mass spectrometry, not immunoassay, which is unreliable at female-range concentrations), free testosterone, sex hormone-binding globulin (SHBG), complete blood count (to watch for polycythemia), lipid panel, and liver function tests.

If total testosterone exceeds 46 ng/dL on a transdermal formulation, the dose should be reduced. If total testosterone exceeds 70 ng/dL, therapy should be stopped temporarily and restarted at a lower dose. With pellets, this kind of real-time dose adjustment is impossible, which is precisely why monitoring becomes an exercise in documenting a problem you cannot fix until the pellet dissolves.

Women should also be monitored for signs of androgenization at every visit: acne, hirsutism (Ferriman-Gallwey score), voice changes (ask the patient, because clinicians may not notice early pitch drops), and clitoral sensitivity changes [5].

The target is symptom improvement at the lowest effective testosterone level. Pellets are engineered for the opposite: maximum depot release over months, with no titration ability. For a 60 kg woman, that pharmacokinetic design is the wrong tool for the clinical job.