Testosterone Cypionate

• Male Hypogonadism
• Testosterone Deficiency
• Primary Hypogonadism

Testosterone cypionate is an injectable form of testosterone used for testosterone replacement therapy in males with conditions associated with testosterone deficiency. It is one of the most commonly prescribed forms of testosterone in the United States.

Mechanism of Action

Testosterone cypionate works as a synthetic androgen:

• Androgen receptor activation: Binds to androgen receptors in target tissues
• Promotes male characteristics: Maintains secondary sexual characteristics
• Anabolic effects: Promotes protein synthesis and muscle growth
• Hematopoietic effects: Stimulates erythropoietin production
• Bone effects: Maintains bone mineral density
• Libido and sexual function: Supports normal sexual function

The cypionate ester allows for slow release, providing sustained testosterone levels.

Available Formulations

Testosterone cypionate is available as:

• Injectable solution: 100 mg/mL, 200 mg/mL in oil (sesame or cottonseed oil)

Administered via intramuscular injection.

Medical Uses

FDA-Approved Indications:

• Testosterone replacement therapy in adult males with conditions associated with deficiency or absence of endogenous testosterone:
  • Primary hypogonadism (congenital or acquired)
  • Hypogonadotropic hypogonadism (congenital or acquired)

Dosing Guidelines

Hypogonadism:

• Initial: 50-400 mg intramuscularly every 2-4 weeks
• Adjust based on serum testosterone levels and clinical response
• Typical maintenance: 100-200 mg every 1-2 weeks or 200-400 mg every 2-4 weeks

Monitoring:

• Measure testosterone levels midway between injections
• Target trough levels typically 400-700 ng/dL

Important Safety Information

Boxed Warning:

• Blood clots in the legs or lungs have occurred with testosterone products
• Seek immediate medical attention for leg pain/swelling or sudden shortness of breath

Contraindications:

• Breast cancer in males
• Known or suspected prostate cancer
• Pregnant women (teratogenic effects)
• Serious cardiac, hepatic, or renal disease

Warnings and Precautions:

• Polycythemia: Monitor hematocrit; discontinue if hematocrit >54%
• Cardiovascular risk: Increased risk of MI and stroke
• Hepatic effects: Peliosis hepatis and hepatic neoplasms (rare)
• Edema: May worsen heart failure
• Sleep apnea: May worsen existing condition
• Prostatic effects: Monitor PSA and prostate
• Abuse potential: Schedule III controlled substance

Drug Interactions

• Oral anticoagulants (warfarin): May increase anticoagulant effect; monitor INR
• Insulin/oral hypoglycemics: May decrease glucose; monitor and adjust doses
• Corticosteroids: May enhance edema; use with caution in cardiac disease
• Oxyphenbutazone: Increased testosterone levels

Special Populations

• Hepatic Impairment: Use with caution; contraindicated in serious liver disease
• Renal Impairment: Use with caution; contraindicated in serious kidney disease
• Cardiac Disease: Use with caution; may worsen edema and heart failure
• Elderly: Monitor for prostate abnormalities and polycythemia
• Women: Contraindicated in pregnancy; may cause virilization
• Pediatric: May accelerate bone maturation without linear growth; use with caution