What is the recommended use and dosage of testosterone cypionate (testosterone replacement therapy) for men with hypogonadism?

Testosterone Cypionate for Hypogonadism in Men

Testosterone cypionate injections at a dose of 50-400 mg every 2-4 weeks are recommended for men with confirmed hypogonadism, defined as symptoms plus two morning testosterone levels <300 ng/dL. 1

Diagnosis of Hypogonadism

• Diagnosis requires:
  • Morning total testosterone concentration <300 ng/dL on at least two separate measurements 2
  • Clinical symptoms consistent with testosterone deficiency 2, 3
  • Measurement of LH and FSH to distinguish primary (testicular) from secondary (pituitary-hypothalamic) hypogonadism 2

Dosage and Administration

• Intramuscular injection only (never intravenously) 1
• Administer deep in the gluteal muscle 1
• Dosage for hypogonadal men: 50-400 mg every 2-4 weeks 1
• Target mid-normal testosterone value (500-600 ng/dL) 2
• Inspect visually for particulate matter before administration 1
• Warming and shaking the vial can redissolve any crystals formed during storage 1

Monitoring

• Test testosterone levels 2-3 months after treatment initiation or dose change 2
• For injections, measure levels midway between injections 2
• Once stable levels achieved, monitor every 6-12 months 2
• Additional monitoring:
  • Hematocrit (risk of erythrocytosis)
  • Prostate health
  • Bone density in men with fracture history or osteoporosis risk factors 2

Safety Considerations

• Recent high-quality evidence from the TRAVERSE study shows testosterone replacement therapy does not increase stroke risk in men 45-80 years with confirmed hypogonadism 4
• Absolute contraindications:
  • Prostate cancer
  • Male breast cancer
  • Desire for fertility in near future 2
• Relative contraindications:
  • Severe obstructive sleep apnea
  • Severe lower urinary tract symptoms
  • Uncontrolled congestive heart failure
  • Hematocrit >54% 2

Clinical Benefits

• Improves sexual function and libido 2
• Enhances quality of life 2
• Increases lean body mass 2
• Reduces abdominal subcutaneous adipose tissue 2
• Improves insulin sensitivity in men with metabolic syndrome 2
• Reduces inflammatory markers 2
• Small improvements in depressive symptoms 2
• May improve energy levels, vitality, and fatigue 2
• Recent landmark trials showed modest but clinically significant benefits on energy, mood, sexual function, and satisfaction 5

Comparative Considerations

• Intramuscular testosterone cypionate has lower cost and less frequent administration compared to other formulations 2
• However, it can cause "roller coaster" effect with fluctuating testosterone levels 2
• Subcutaneous testosterone enanthate may offer lower post-therapy estradiol and hematocrit levels compared to intramuscular testosterone cypionate 6
• Transdermal preparations (gels, patches) provide more stable serum levels but at higher cost 2

Important Pitfalls to Avoid

• Don't diagnose hypogonadism based on a single testosterone measurement
• Don't initiate therapy without confirming low testosterone with two morning measurements
• Don't forget to measure LH and FSH to determine the cause of hypogonadism
• Don't administer testosterone cypionate intravenously (intramuscular use only)
• Don't overlook monitoring for adverse effects, particularly hematocrit elevation
• Don't continue therapy without periodic reassessment of benefits and risks