CJC-1295 (no DAC) common uses, half-life, side effects and more

Also known as Mod GRF 1-29

About

Modified GRF 1-29 is a synthetic version of the first 29 amino acids of the hormone that tells the pituitary to release growth hormone. Four changes to the sequence protect it from the enzymes that break down the natural hormone. It has never been an approved drug anywhere. It is sold under the name CJC-1295 without DAC. That name is a misnomer. CJC-1295 was coined for a different molecule carrying an extra albumin-binding tail that is part of its definition. The two peptides are sold under one name and behave very differently. This one lasts minutes and the other lasts about a week.

Common uses

  • Recovery, sleep, and body composition (community use)
  • Raising growth hormone without injecting growth hormone itself
  • Stacking with a growth hormone releasing peptide
  • Countering the age-related decline in growth hormone

Frequency

One to three times daily in community practice

Dosing

Community practice is about 100 mcg injected under the skin one to three times a day. That figure matches the dose used for a diagnostic pituitary test given into a vein rather than any therapeutic dose. It is roughly a twentieth of the only established subcutaneous dose in this family. The widely repeated claim that about 100 mcg saturates the pituitary is not a safety ceiling. Measured peak growth hormone plateaus at about a tenth of that dose. Higher doses did not raise the peak but did keep growth hormone elevated for longer. The long-acting relative produced dose-dependent rises at roughly twenty-four to forty-eight times the supposed ceiling.

Half-life

No human study has measured how long this peptide lasts in the blood. The figures quoted online come from other molecules. The closest measured relatives are sermorelin at roughly 4 to 12 minutes and tesamorelin at 8 to 11 minutes on its label. Only one of the four sequence changes has been measured in people and it added about two minutes. This is a minutes-scale peptide rather than an hours-scale one. The growth hormone rise starts within about 15 minutes and is largely over within about two hours.

Storage

The only labeled peptide in this family is mixed with sterile water rather than bacteriostatic water and used immediately rather than stored. The common practice of mixing with bacteriostatic water and refrigerating for weeks has no label behind it.

Side effects

  • Injection-site redness or itching
  • Flushing or warmth shortly after injection
  • Lightheadedness or tingling shortly after injection
  • Water retention, joint aches, and tingling hands reported at low rates for the approved relative
  • Drowsiness when dosed at bedtime

How it works

Modified GRF 1-29 activates the growth hormone releasing hormone receptor on the pituitary. That makes the pituitary both produce and release its own growth hormone. The growth hormone then raises IGF-1 from the liver. Because the signal runs through your own pituitary the effect is capped by what your pituitary can produce. The four sequence changes block the enzyme that clips the natural hormone, stop it rearranging in solution, raise receptor binding, and prevent oxidation in the vial. It is often claimed that a short-acting peptide preserves natural growth hormone pulses while the long-acting version flattens them into a plateau. The one study that measured this found the long-acting version left pulse frequency and size unchanged and simply raised the level between pulses. Nobody has measured pulses on this peptide at all.

Research quality

No human study of this peptide has ever been published. A 2026 review that grades these compounds places it in the lowest evidence tier and notes that even its route of administration has never been reported in a peer-reviewed human study. Everything known about it is inferred from relatives. Sermorelin was an approved drug and was withdrawn for commercial reasons rather than for safety. Tesamorelin is approved and is the only member of the family still marketed. The long-acting version has two small trials in healthy adults. None of that evidence was generated with this molecule.

Warnings

  • It is banned in sport at all times and is named on the prohibited list rather than caught by a general clause
  • Growth hormone and IGF-1 drive cell growth so it is not for anyone with a current or past cancer
  • Drugs in this family push IGF-1 above the normal range in roughly half of users and the long-term effect of that is unknown
  • It can raise blood sugar so caution in diabetes or insulin resistance is sensible
  • The name on the vial belongs to a different and far longer-lasting molecule so what arrives may not be what was intended
  • Avoid it in pregnancy and breastfeeding since no data exist

Sources (8)

  • Human growth hormone releasing factor conjugate that binds serum albumin, the paper that named CJC-1295 (Jette et al.)

    Endocrinology 2005 (PMID 15817669)

  • Enhanced stability and potency of GRF analogues, the rationale for three of the four substitutions (Campbell et al.)

    Peptides 1994 (PMID 7937325)

  • Half-life of the D-Ala2 substitution measured against unmodified GRF(1-29) in normal men (Soule et al.)

    Journal of Clinical Endocrinology and Metabolism 1994 (PMID 7962295)

  • Growth hormone releasing peptide acts synergistically with growth hormone releasing hormone in normal men (Bowers et al.)

    Journal of Clinical Endocrinology and Metabolism 1990 (PMID 2108187)

  • Pulsatile growth hormone secretion persists during continuous stimulation by CJC-1295 (Ionescu and Frohman)

    Journal of Clinical Endocrinology and Metabolism 2006 (PMID 17018654)

  • Prolonged stimulation of growth hormone and IGF-1 by the DAC-linked CJC-1295 in healthy adults (Teichman et al.)

    Journal of Clinical Endocrinology and Metabolism 2006 (PMID 16352683)

  • Evidence grading of growth hormone secretagogues, placing this peptide in the lowest tier with no human studies

    Frontiers in Endocrinology 2026

  • Tesamorelin prescribing information, the only approved GHRH analog and the closest labeled comparator

    US prescribing information for EGRIFTA SV

PubMed search terms (4)

Related

Quick facts
Category
Growth Hormone Sleep Muscle
Routes
Subcutaneous
Legal status
Research use only Gray market Banned in sport
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