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Basics & Technique

When should I inject sermorelin?

Updated 2026-05-05

Inject sermorelin once at night, 60-90 minutes after your last meal and 30 minutes before sleep. This timing matches your body's natural growth hormone pulse, which happens during deep sleep. Eating raises insulin and blood sugar, both of which blunt growth hormone release - so dosing on a relatively empty stomach is important. Sermorelin works fast and clears fast (half-life is about 11-20 minutes), so it does its job in one short window each night.

IfIf you ate a big meal less than 90 minutes ago
Thenthen wait until you are closer to fasted before injecting
IfIf you train at night and want sermorelin too
Thenthen inject after the workout, after the post-workout meal has cleared
IfIf you wake up groggy or have vivid dreams that disturb sleep
Thenthen move the dose 30-60 minutes earlier
IfIf you cannot dose at night for any reason
Thenthen a morning fasted dose is the second-best option, though less aligned with your GH pulse
Key facts
  • Sermorelin's half-life is about 11-20 minutes - it acts in a single short pulse
  • Largest natural GH pulses happen in the first hour or two of deep sleep
  • High insulin and high blood sugar both blunt growth hormone release
  • Most clinical protocols dose 100-300 mcg once nightly
  • Sermorelin was approved in the US under the brand Geref in 1997 for pediatric growth hormone deficiency; the brand was discontinued in 2008 for business reasons, not safety
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