For research purposes only. All compounds sold by Ripped Labz are intended for laboratory research use and are not for human consumption.

Post-cycle therapy (PCT) is one of the most critical — and most searched — topics in SARMs research. Because SARMs suppress endogenous testosterone production to varying degrees, a structured PCT protocol is an essential component of any responsible research design. This guide covers the science behind SARMs-induced suppression, how PCT works, and how to structure a protocol after common SARMs cycles.

Why Do SARMs Require PCT?

SARMs bind to androgen receptors and activate anabolic signalling pathways. This activity is detected by the hypothalamic-pituitary-gonadal (HPG) axis, which responds by reducing its own output of luteinising hormone (LH) and follicle-stimulating hormone (FSH) — the signals that drive endogenous testosterone production. The result is suppression of the body's natural hormonal output during the cycle.

The degree of suppression varies by compound, dose, and cycle length:

• LGD-4033 — known to cause significant, dose-dependent suppression; one of the more suppressive SARMs in the literature
• RAD-140 — moderate suppression; potent but generally considered less suppressive than LGD-4033 at equivalent doses
• MK-2866 (Ostarine) — mild suppression at lower doses; more pronounced at higher doses or longer cycles
• MK-677 — not a SARM; operates as a growth hormone secretagogue and does not suppress the HPG axis

What Is PCT?

Post-cycle therapy refers to a protocol designed to restore the HPG axis to normal function after a suppressive cycle. In research contexts, PCT compounds typically include selective oestrogen receptor modulators (SERMs) such as Nolvadex (tamoxifen) or Clomid (clomiphene), which block oestrogen receptors at the pituitary and hypothalamus, prompting the body to resume LH and FSH production.

PCT Protocol Structure After a SARMs Cycle

The appropriate PCT protocol depends on the suppression level of the compounds used:

Mild Suppression (e.g., MK-2866 solo, short cycle)

• Some researchers opt for a natural recovery period of 4–6 weeks with no PCT compounds
• Others use a light SERM protocol (e.g., Nolvadex at lower doses) for 4 weeks as a precaution

Moderate Suppression (e.g., RAD-140 solo, 8–10 weeks)

• Standard PCT: Nolvadex 40/40/20/20 (mg per week over 4 weeks) or Clomid 50/50/25/25
• Begin PCT approximately 2 weeks after the last dose to allow clearance

Heavy Suppression (e.g., LGD-4033 solo or stacked cycle, 10–12 weeks)

• Full PCT: Clomid 50/50/25/25 or Nolvadex 40/40/20/20, potentially combined
• Some protocols extend to 6 weeks for heavily stacked cycles
• Bloodwork before and after is strongly recommended in research design

PCT Timing: When to Start

PCT timing depends on the half-life of the SARMs used:

• RAD-140 (half-life ~16–20 hours) — begin PCT approximately 24–48 hours after last dose
• LGD-4033 (half-life ~24–36 hours) — begin PCT approximately 48–72 hours after last dose
• MK-2866 (half-life ~24 hours) — begin PCT approximately 24–48 hours after last dose

Supporting Recovery During PCT

Beyond SERM compounds, research protocols often include supportive variables during PCT:

• Zinc and Vitamin D — both play roles in testosterone biosynthesis pathways
• Ashwagandha — studied for its effects on cortisol and LH levels
• Sleep and recovery optimisation — the majority of LH pulses occur during sleep; sleep quality is a meaningful variable in HPG axis recovery research

SARMs for Your Research Protocol

Browse the full Ripped Labz SARMs range to source compounds for your research:

• Original SARMs Range (High mg)
• Nutrition SARMs Range (Lower mg)
• Beginner Muscle Stack (LGD-4033 / RAD-140)
• Advanced Muscle Stack (LGD-4033 / RAD-140 / MK-677 / MK-2866)

Also see our related guides: SARMs Stacking Guide | RAD-140 vs LGD-4033 Comparison

All Ripped Labz SARMs are for research purposes only and are not intended for human consumption. Always follow applicable regulations in your jurisdiction.