Testosterone Replacement Therapy and Hair Loss

Key Evidence from Guidelines

The American College of Physicians, as reported in the New England Journal of Medicine, states that there is no evidence that testosterone replacement therapy (TRT) at physiologic doses causes or accelerates male-pattern baldness (androgenetic alopecia) 1, 2, 3
The New England Journal of Medicine explicitly states that there is no data indicating acceleration of male-pattern baldness in men receiving testosterone-replacement therapy, although this possibility has not been carefully studied 1, 2, 3
Comprehensive guidelines on TRT monitoring and risks list adverse effects including polycythemia and erythrocytosis 1, prostate effects and PSA elevation 1, 2, sleep apnea exacerbation 1, 2, 3, skin reactions (erythema, pruritus in up to 66% with patches) 1, 2, 3, and breast tenderness and testicular atrophy 1, 2, 3

Guidelines for female-to-male transition using testosterone therapy list androgenic alopecia as a common expected effect, but this occurs in the context of supraphysiologic testosterone levels (targeting 300-1,000 ng/dL) and patients with no prior androgen exposure (biological females) 4

The American College of Physicians, as reported in the New England Journal of Medicine, recommends reassuring patients that guideline-level evidence does not support TRT causing hair loss at replacement doses 1, 2, 3
Targeting mid-normal testosterone range (not supraphysiologic levels) is recommended to optimize safety 1, 2, 3
Avoiding supraphysiologic testosterone dosing is recommended, as it increases adverse effects without additional benefit and may theoretically increase androgenic effects on hair follicles 4

The comprehensive TRT monitoring protocol does not include hair loss assessment as a standard parameter, and recommends baseline monitoring of PSA, hematocrit/hemoglobin, and digital rectal exam 1, 2, 3
Follow-up monitoring is recommended at 1-2 months, then every 3-6 months in the first year, and then yearly, with monitoring of testosterone levels, PSA, hematocrit, voiding symptoms, and sleep apnea 1, 2, 3