1. General
1.1. T -> DHT (active form) via 5 alpha-reductase
1.2. Testicular androgens
1.2.1. Secreted by Leydig cells via LH stimulation
1.3. Ovarian and adrenal androgens
1.3.1. converted to T peripherally
2. Testosterone
2.1. Actions
2.1.1. Growth and maturation of male genitalia and 2nd sexual characteristics
2.1.2. Nitrogen retention
2.1.2.1. increase muscle strength, bone growth, RBC and erythropoietin production, decreased HDL
2.1.2.2. Anabolic steroids on work if on a high protein diet and w/ strenuous exercise (need neg N balance)
2.2. MOA
2.2.1. Binds cytoplasmic receptor
2.2.1.1. Complex transported to nucleus
2.2.1.1.1. Protein transcription
2.2.2. Circulates bound to SHBG or albumin
2.3. Excretion via kidney
2.4. SE
2.4.1. Masculinization
2.4.2. Growth disturbance
2.4.2.1. Cause premature closure of epiphysis
2.4.3. Jaundice, hepatitis, hepatic Ca
2.4.3.1. Oral steroids only! (oxandrolone, methyltestosterone, etc)
2.4.3.2. Echinacea increases risk
2.4.4. Spermatogenesis
2.4.4.1. Neg feedback on GnRH and FSH
2.4.5. Tendon rupture
2.4.5.1. Muscle strength increases, but tendon strength doesn't!
2.4.6. serum PSA
2.4.6.1. Possible FP BPH testing
2.4.7. DD interactions
2.4.7.1. Bleeding in pts on warfarin
2.4.7.2. metabolism of oral hypoglycemics
2.5. Use
2.5.1. Hypogonadism
2.5.1.1. HRT
2.5.2. Growth stimulation
2.5.2.1. In combo w/ GH
2.5.3. Protein anabolic agents
2.5.3.1. reverse protein loss after trauma, surgery, or prolonged immobilization
2.5.4. Adjunct Tx for breast carcinoma
2.5.5. Endometriosis
2.5.5.1. Danazol inhibits mid-cycle LH/FSH surge
2.5.5.1.1. E production
2.5.6. Hypoactive sexual desire disorder in women
3. Antiandrogens
3.1. Androgen receptor antagonists
3.1.1. Flutamide
3.1.2. Spironolactone
3.1.2.1. (also a K-sparing diuretic, but androgen antag too!)
3.1.3. MOA
3.1.3.1. antagonize T at receptor
3.1.3.2. Cyproterone also has progestational effect
3.1.3.2.1. suppresses LH and FSH to decrease androgen effect
3.1.4. Use
3.1.4.1. Hirsutism
3.1.4.2. excessive sexual drive in men
3.1.4.2.1. Chemical castration
3.1.4.3. Prostate cancer
3.1.5. SE
3.1.5.1. Black box warning: Nilutamide causes interstitial pneumonitis)
3.1.5.2. Gynecomastia and mild hepatotox (Flutamide only)
3.2. Reductase inhibitors
3.2.1. Finasteride
3.2.2. Dutasteride
3.2.3. MOA
3.2.3.1. Inhibit 5 alpha-reductase
3.2.3.1.1. can't convert T -> DHT
3.2.4. Use
3.2.4.1. BPH
3.2.4.2. Male pattern baldness
3.2.4.2.1. Finasteride only (Propecia)
3.2.5. SE
3.2.5.1. Decreased libido and impotence
3.2.5.2. Possible decrease in risk of prostate ca
3.2.5.2.1. Finasteride only
3.3. Ketoconazole
3.3.1. MOA
3.3.1.1. antifungal that inhibits steroid synthesis
3.3.2. Use
3.3.2.1. prevent hirsutism in PCOD
3.3.3. Se
3.3.3.1. Tox limits use
3.3.3.1.1. Will turn of synth of ALL steroids
3.4. Leuprolide
3.4.1. GnRH analogue
3.4.1.1. Tx for prostate cancer
3.5. Saw Palmetto
3.5.1. Relieves Sx of BPH (questionable efficacy)