What are the effects of a 17-year-old male taking 1mg of Anastrozole (generic name) every 3 days for 10 doses?

Anastrozole Use in a 17-Year-Old Male: Critical Safety Concerns

A 17-year-old male should not take anastrozole 1mg every 3 days for 10 doses due to serious risks to bone health, growth plate closure, and lack of any evidence supporting safety or efficacy in adolescent males. This represents dangerous off-label use in a population where the drug has never been studied and poses significant harm to skeletal development during a critical growth period.

Why This Is Contraindicated

Approved Indications Do Not Include Adolescent Males

• Anastrozole is FDA-approved exclusively for postmenopausal women with breast cancer, not for any male population, and certainly not for adolescents 1
• All clinical trial data involves postmenopausal women aged 40-70 years, with no safety or efficacy data in males under 18 years 1

Critical Bone Health Risks in Adolescents

• Anastrozole significantly decreases bone mineral density in both lumbar spine and hip, with fracture rates of 7.1% observed even in adult women 2
• In a 17-year-old male still undergoing skeletal maturation, profound estrogen suppression would catastrophically impair bone mineralization during peak bone mass acquisition 2
• Severe osteoporosis (T-score <-4) is an absolute contraindication to anastrozole use, and adolescents have not yet achieved peak bone mass 1, 2
• The increased fracture risk documented in adults (spine, hip, wrist) would be magnified in an adolescent whose bones are still developing 2

Growth Plate and Skeletal Maturation Concerns

• Estrogen is essential for growth plate closure and normal skeletal maturation in males 3
• Blocking aromatase prevents testosterone conversion to estradiol, which could delay or abnormally affect epiphyseal closure 3
• Even 10 doses (approximately 30 days of treatment) could disrupt normal pubertal bone development during this critical window

What Would Happen During 10 Doses

Hormonal Effects (Days 1-30)

• Anastrozole would block conversion of testosterone to estradiol, causing estradiol levels to drop significantly (by approximately 58-60% based on adult data) 3, 4
• Testosterone levels might initially increase as aromatization is blocked, but this creates an abnormal hormonal milieu for an adolescent 3

Musculoskeletal Symptoms

• Joint stiffness and arthralgias occur in 25-30% of adult patients and would likely manifest even in this short timeframe 2, 5
• These symptoms are severe enough to cause treatment discontinuation in adults and would be particularly problematic for an active adolescent 2, 5

Bone Density Changes

• While measurable bone density loss typically requires longer exposure, the biological process of impaired bone mineralization would begin immediately 2
• At 17 years old, during peak bone mass acquisition, even brief interruption of normal estrogen signaling could have lasting consequences 2

Other Adverse Effects

• Vasomotor symptoms (hot flashes, night sweats) would likely occur 1, 2
• Potential for hypertension, hypercholesterolemia, and cardiovascular effects documented in adults 2
• Risk of mood changes and depression 2

Absolute Requirements If This Were Ever Considered (Which It Should Not Be)

Mandatory Pre-Treatment Assessment

• Baseline bone mineral density measurement via DEXA scan would be absolutely required 1, 2, 3
• Baseline lipid panel and cardiovascular assessment 2
• Documentation of Tanner stage and growth plate status via bone age X-ray
• Baseline estradiol and testosterone levels 3

Bone Protection Measures

• Calcium and vitamin D supplementation would be mandatory 1, 2, 5
• Regular weight-bearing exercise 1, 2, 5
• Consideration of bisphosphonates or RANKL inhibitors, though these also have unknown effects in adolescents 2, 5

Clinical Context: Why Adolescents Might Seek This

Misguided Use for Height Increase

• Some adolescents or parents mistakenly believe aromatase inhibitors can delay growth plate closure to increase final height
• This approach is not evidence-based and risks permanent skeletal harm 2

Bodybuilding or Athletic Misuse

• Adolescent males may seek anastrozole to prevent gynecomastia while using anabolic steroids
• This represents dangerous polypharmacy with compounded risks to bone health, cardiovascular function, and endocrine development 2, 3

Gynecomastia Treatment

• Pubertal gynecomastia is physiologic and self-limited in most cases
• Anastrozole is not indicated for this condition and the risks far outweigh any theoretical benefit 3

The Bottom Line

Even 10 doses of anastrozole 1mg every 3 days (total exposure ~30 days) poses unacceptable risks to a 17-year-old male's skeletal development, with potential for permanent impairment of bone health during a critical growth period. The drug has zero evidence supporting safety in this population, and all available data demonstrates significant bone toxicity even in adults 1, 2. Any healthcare provider considering this prescription would be practicing outside the standard of care and exposing the patient to serious harm without any established benefit.