Luteinizing Hormone

When high

When to investigate further:

• Elevated LH (>12) with low testosterone off-cycle: primary hypogonadism (testicular failure)

When low

On AAS/TRT (LH suppressed <0.5 IU/L):

• Expected and unavoidable -- exogenous androgens suppress GnRH, which suppresses LH
• HCG -- 250-500 IU EOD or 500-1000 IU 2x/week on cycle to mimic LH and maintain testicular size/function
• HCG does NOT restore pituitary LH -- it acts directly on Leydig cells as an LH analogue
• Do NOT exceed 1500 IU per injection -- desensitises Leydig cell LH receptors

PCT (stimulating LH recovery):

• Enclomiphene -- 12.5-25mg/day for 4-6 weeks (preferred SERM; fewer side effects than clomiphene; directly stimulates pituitary LH release by blocking hypothalamic estrogen feedback)
• Tamoxifen (Nolvadex) -- 20mg/day for 4-6 weeks (blocks estrogen at hypothalamus/pituitary, upregulates GnRH and LH)
• Clomiphene (Clomid) -- 25-50mg/day for 4-6 weeks (stimulates LH/FSH but more side effects: mood, vision disturbance)
• HCG bridge -- 500 IU EOD for 2 weeks BEFORE starting SERM PCT to restore testicular sensitivity after prolonged suppression

Supplements (supporting natural LH recovery):

• D-Aspartic Acid -- 3g/day (may transiently boost LH in hypogonadal men; modest effect)
• Zinc -- 30mg/day (required cofactor for LH signalling at the Leydig cell)
• Vitamin D3 -- 5000 IU/day (deficiency impairs GnRH pulsatility)

Timeline expectations:

• LH typically begins recovering 2-4 weeks into PCT with SERMs
• Full HPTA recovery: 4-12 weeks for short cycles, 3-6+ months for long/heavy cycles
• If LH remains <1.0 IU/L after 3 months off all compounds, investigate secondary hypogonadism

When to investigate further:

• LH persistently suppressed off-cycle despite PCT: MRI pituitary to rule out adenoma