Post-Cycle Therapy (PCT) Guide 2026: How to Use HCG, SERMs & Ancillaries After Any Steroid Cycle Ireland

Post-cycle therapy is not optional. It is the most critical phase of any performance enhancement cycle, and skipping it is the single most reliable way to undo everything you worked for — and potentially compromise your long-term hormonal health.

This guide covers the complete science and protocol of PCT: why the Hypothalamic-Pituitary-Testicular Axis shuts down during a cycle, how HCG, Letrozole, and SERMs work to restart it, and exactly which protocol to run based on your cycle type and compounds.

Why Your Testosterone Shuts Down During a Cycle

The HPTA operates via negative feedback. When exogenous testosterone (or any suppressive compound) is detected by the hypothalamus and pituitary, they respond by reducing output of GnRH, LH, and FSH — the hormones that signal the testes to produce testosterone and maintain spermatogenesis.

The longer and higher the dose of the suppressive compound, the deeper and longer the suppression. After a 12-week testosterone cycle at 500mg/week, LH and FSH production can remain suppressed for 3-6 months without intervention. During this time, the user exists in a hypogonadal state — low testosterone, fatigue, libido loss, mood instability, and accelerated muscle loss. This is why PCT is non-negotiable.

The Three Pillars of PCT

1. HCG (Human Chorionic Gonadotropin)

HCG is a glycoprotein hormone that mimics LH at the testicular level. During a steroid cycle, prolonged LH absence causes the Leydig cells in the testes to atrophy — they downregulate their receptor density and steroidogenic capacity. HCG prevents this atrophy by maintaining Leydig cell stimulation even in the absence of endogenous LH.

Protocol options:

• On-cycle HCG: 250IU twice weekly throughout the cycle — prevents testicular atrophy and dramatically speeds HPTA recovery
• Post-cycle HCG: 500IU every other day for 10 doses (2 weeks), beginning 24-72 hours after last injection — used when on-cycle HCG was not implemented

Our HCG 5000IU vials provide exactly enough for a standard post-cycle protocol. Each 5000IU vial, when mixed with bacteriostatic water, provides 10 x 500IU doses.

2. SERMs (Selective Estrogen Receptor Modulators)

After HCG priming, SERM therapy is the foundation of PCT. SERMs act at the hypothalamic and pituitary levels, blocking estrogen receptors that normally suppress GnRH and LH secretion. This removes the feedback brake and allows LH and FSH to rise, signaling the now-primed testes to resume testosterone production.

Nolvadex (Tamoxifen) Protocol: 20mg/day for weeks 1-2, then 10mg/day for weeks 3-4

Clomid (Clomiphene) Protocol: 50mg/day for weeks 1-2, then 25mg/day for weeks 3-4

Both Nolvadex and Clomid are effective. Many practitioners favor Nolvadex for its more favorable mood and vision side-effect profile. Some advanced users run both simultaneously at lower doses for synergistic HPTA stimulation.

3. Estrogen Management During PCT

During PCT, as testosterone begins recovering, aromatization will also resume. However, artificially suppressing estrogen too aggressively during PCT is counterproductive — estrogen plays a role in LH receptor upregulation and general recovery. Letrozole at PCT doses should be used cautiously, especially if bloodwork shows excessive E2 elevation.

Femara (Letrozole) 2.5mg, taken at 0.5-1.25mg every other day during PCT only when bloodwork indicates estrogen elevation, is our recommended approach.

PCT Protocols by Cycle Type

After a Short SARM Cycle (8 weeks LGD-4033 or S-4)

• No HCG phase required for most users
• Nolvadex 20mg/day for 4 weeks
• Bloodwork at week 6 post-PCT to confirm recovery

After a Standard Testosterone Cycle (12 weeks Test E, 300-500mg/week)

• Wait 14-16 days after the last injection for the ester to clear
• HCG 500IU EOD x 10 doses (2 weeks)
• Nolvadex 20mg/day x 2 weeks, then 10mg/day x 2 weeks
• Bloodwork at week 6 post-PCT

After a Heavy or Long Cycle (16+ weeks, 600mg+ per week)

• HCG 500IU EOD x 3 weeks (15 doses)
• Clomid 50mg/day + Nolvadex 20mg/day x 2 weeks (combo PCT)
• Then Nolvadex 10mg/day x 4 weeks
• Letrozole 0.5mg EOD if estrogen is elevated on bloodwork
• Bloodwork at week 8 post-PCT

Signs of Poor HPTA Recovery

If bloodwork at 6-8 weeks post-PCT shows testosterone remains below 400ng/dL with LH and FSH still suppressed, repeat the SERM phase. Consult an endocrinologist or men’s health specialist if suppression persists beyond 6 months.

Warning signs of inadequate recovery that should prompt immediate bloodwork:

• Persistent fatigue disproportionate to sleep quality
• Severe libido loss beyond 8 weeks post-cycle
• Depression or marked mood instability
• Inability to maintain muscle mass despite adequate training and nutrition

What Happens If You Skip PCT?

Users who skip PCT after suppressive cycles experience the full hypogonadal withdrawal syndrome. Beyond the immediate discomfort of low testosterone symptoms, prolonged low-T periods can result in:

• Loss of a significant portion of cycle gains as anabolic signaling disappears
• Testicular atrophy that may become semi-permanent without treatment
• Fertility impairment — sperm production depends on adequate FSH; suppression can last years
• Psychological dependency on exogenous hormones

PCT compounds are available in our store. Always order your PCT compounds before your first cycle day — you should never start a suppressive cycle without your PCT on hand. Post-cycle therapy guide.