T-04
Injection timing planner
Sermorelin's trials did not dose at random times: the pediatric label regimen and the adult studies injected at bedtime, riding the sleep-onset growth hormone pulse.
Sermorelin's trials did not dose at random times: the pediatric label regimen and the adult studies injected at bedtime, riding the sleep-onset growth hormone pulse. This planner explains that physiology, shows what the timing experiments found, and builds a printable injection-site rotation schedule from published technique recommendations.
Worked example
Example: with a ten-thirty bedtime, the trial-consistent injection window falls shortly before lights out, because the largest natural GH pulse follows sleep onset with the first slow-wave sleep episode (Van Cauter 1996). A simple rotation runs the four abdominal quadrants in a fixed order, one per night, each injection at least a finger's width from the last, per published technique recommendations (Frid 2016).
Step by step
- Pick your usual bedtime; consistency matters more than the exact hour.
- Place the injection shortly before bed, matching how the trials dosed.
- Rotate sites in a fixed pattern across abdominal quadrants or thighs, never repeating the exact spot on consecutive injections.
- Log each site and date; the printable grid exists so drift shows up.
- Review the pattern with your prescriber or pharmacist at each refill.
What the timing experiments actually showed
| Protocol | Timing | Finding | Source | Source |
|---|---|---|---|---|
| IV GHRH during 3rd REM period | Late night | Near 10-fold slow-wave sleep increase | Kerkhofs 1993 | source |
| IV GHRH 04.00-07.00 h | Early morning | GH rose; slow-wave sleep did not | Schier 1997 | source |
| Nightly SC analog, 16 weeks | 2100 h | GH pulse within 10 min, about 2 h duration; sleep quality unchanged | Khorram 1997 | source |
| Physiology review | Sleep onset | Largest GH pulse rides the first slow-wave sleep episode; about 70% of male sleep GH pulses coincide with SWS | Van Cauter 1996 | source |
Frequently asked questions
Does injection time really matter?
Yes, experimentally: late-night GHRH raised slow-wave sleep while the same peptide in the early morning did not Schier 1997, and the efficacy trials dosed at night. Bedtime aligns the injected signal with the axis's own rhythm Van Cauter 1996.
Yes, and this is one of the few sermorelin questions with direct experimental evidence. Identical GHRH exposures produced different results by clock time: late-night administration increased slow-wave sleep markedly Kerkhofs 1993, while early-morning administration raised GH and left sleep untouched Schier 1997.
The label-era pediatric regimen and the adult trials all injected at bedtime Thorner 1996. If sermorelin is used at all, the trial-consistent pattern is nightly, before bed, at a consistent hour.
Why rotate injection sites?
Repeated injections into one spot cause lipohypertrophy, a fat-pad thickening that can distort absorption; published technique guidance recommends systematic rotation with each injection spaced from the last Frid 2016. The planner's grid makes rotation automatic.
Because subcutaneous tissue keeps score. Injecting the same spot repeatedly produces lipohypertrophy, a rubbery thickening documented across injectable therapies that can alter how reliably a dose absorbs; published recommendations call for systematic rotation with consecutive injections spaced apart Frid 2016.
The printable grid in this planner exists to make rotation a habit rather than an intention, and it doubles as the log your prescriber will actually want to see.
What happens if a night is missed?
Little, physiologically: sermorelin clears in minutes Soule 1994 and each injection is an independent prompt to an axis running its own rhythm. Do not double up; resume the normal pattern the next night and mention repeated misses to your prescriber.
The pharmacology is forgiving here: sermorelin clears in minutes Soule 1994, each injection is an independent prompt, and the axis returns to its own rhythm between doses. A missed night means one un-prompted night, not accumulation or withdrawal.
The practical rule every injectable therapy converges on applies: do not inject a double dose to compensate, resume the usual schedule, and tell your prescriber if misses become a pattern, because dosing density is what separated IGF-1 responders from non-responders in the trials Vittone 1997.
Tools: educational calculators and references only.