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How do I cycle GHK-Cu on and off?

Updated 2026-05-05

Most GHK-Cu protocols run 30-60 days on, then 30-60 days off. The off period exists to let copper levels normalize, since you are adding copper to your body every time you inject. Some protocols also use 5 days on, 2 days off inside each cycle to keep the daily exposure lower. There is no human trial that proves this cycling pattern is needed; it is precaution borrowed from how the body handles copper, not a safety rule. If you are short on time, even a 4 week on / 4 week off cadence is reasonable.

IfIf you are doing general anti-aging or recovery
Thenthen 30 days on, 30 days off is the most common community protocol
IfIf you have an injury you are healing
Thenthen 10-14 days daily is often enough; reassess before continuing
IfIf you take a copper-containing multivitamin
Thenthen count it toward your total copper load and consider pausing during the GHK-Cu phase
IfIf you have Wilson''s disease or another copper metabolism disorder
Thenthen do not cycle GHK-Cu at all - it is contraindicated
Key facts
  • The cycle exists for copper load management, not for receptor desensitization
  • Daily dietary copper intake from food is typically 1-2 mg; injecting 1-2 mg roughly doubles your daily copper exposure
  • Total body copper is about 80-100 mg, with the liver as the primary regulator
  • Some protocols mix GHK-Cu with non-copper peptides during the off cycle (e.g. BPC-157, TB-500) for continued recovery
  • No peer-reviewed human trial has tested optimal injectable GHK-Cu cycling; cycling guidance comes from compounding pharmacy protocols
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