The GH Peptide Landscape
There are six growth hormone peptides worth knowing about. Each stimulates your pituitary gland to release growth hormone — but they differ dramatically in mechanism, side effects, convenience, and cost. This guide compares them head-to-head so you can choose the right protocol for your goals.
The Two Receptor Pathways
Every GH peptide works through one of two receptor systems on the anterior pituitary:
GHRH Receptor Pathway (Growth Hormone-Releasing Hormone):
- CJC-1295 (with and without DAC)
- Sermorelin
These tell the pituitary to produce and prepare GH for release. They’re the “volume knob.”
GHS-R1a / Ghrelin Receptor Pathway (Growth Hormone Secretagogue Receptor):
- Ipamorelin
- GHRP-2
- GHRP-6
- Hexarelin
- MK-677
These trigger the actual release of stored GH. They’re the “trigger.”
The key insight: Combining one peptide from each pathway (GHRH + GHRP) produces synergistic GH release — 3–5x greater than either alone. This is why the CJC-1295 + Ipamorelin stack is standard.
Head-to-Head Comparison
The Master Table
| Feature | CJC-1295 (no DAC) | Ipamorelin | MK-677 | GHRP-2 | GHRP-6 | Sermorelin |
|---|---|---|---|---|---|---|
| Pathway | GHRH | Ghrelin | Ghrelin | Ghrelin | Ghrelin | GHRH |
| Route | Injectable | Injectable | Oral | Injectable | Injectable | Injectable |
| Dosing | 2–3x daily | 2–3x daily | Once daily | 2–3x daily | 2–3x daily | 1–3x daily |
| Half-life | ~30 min | ~2 hours | ~24 hours | ~15 min | ~20 min | ~10 min |
| GH output | Moderate | Moderate | High (sustained) | High | High | Low-moderate |
| IGF-1 boost | 30–50% | 20–40% | 40–90% | 30–60% | 30–60% | 15–30% |
| Cortisol | None | None | None | Mild increase | Moderate increase | None |
| Prolactin | None | None | None | Mild increase | Mild increase | None |
| Hunger | None | Minimal | Significant | Moderate | Severe | None |
| Water retention | Mild | Mild | Moderate-high | Moderate | Moderate | Mild |
| Insulin impact | Minimal | Minimal | Worsens over time | Mild | Mild | Minimal |
| Desensitization | Minimal | Minimal | None | Moderate | Moderate | Moderate |
| Human data | Yes | Yes (Phase II) | Extensive | Yes | Yes | Yes (FDA path) |
| Cost/month | $50–100 | $50–100 | $30–60 | $40–80 | $30–60 | $150–300 |
| Convenience | Low | Low | Very high | Low | Low | Low |
CJC-1295 (no DAC) — The Amplifier
Best for: Anyone running a GH peptide stack. CJC-1295 is almost never run alone — it’s the GHRH half of the standard combo.
Strengths: Clean GH amplification, no cortisol/prolactin effects, pulsatile pattern preserves physiology. Weaknesses: Requires 2–3 daily injections, must be stacked with a GHRP for meaningful results.
Full protocol: CJC-1295 Protocol
Ipamorelin — The Clean Trigger
Best for: Users who want GH optimization with the minimum possible side effects. The safest GHRP available.
Strengths: Highly selective — doesn’t touch cortisol, prolactin, or ACTH. Minimal hunger. No desensitization at standard doses. Weaknesses: Less raw GH output than GHRP-2 or Hexarelin. Requires injection. Not effective enough alone.
Full protocol: Ipamorelin Protocol
MK-677 (Ibutamoren) — The Convenience King
Best for: Users who want GH elevation without needles. Sleep optimization. Appetite stimulation (underweight populations, hardgainers).
Strengths: Oral, once daily, no reconstitution, strongest clinical evidence base, no pituitary desensitization even after 2 years, cheapest option. Weaknesses: Significant hunger spikes, worsens insulin sensitivity over time, non-pulsatile GH pattern, water retention more pronounced than injectables.
Full protocol: MK-677 Protocol
GHRP-2 — The Middle Ground
Best for: Users who want stronger GH output than Ipamorelin and can tolerate mild cortisol/prolactin elevation. Sometimes used in clinical settings.
Strengths: Strong GH release, well-studied, potent synergy with GHRH analogs. Weaknesses: Elevates cortisol and prolactin (dose-dependent). Moderate appetite increase. Shows some desensitization with continuous use.
GHRP-6 — The Hunger Machine
Best for: Underweight individuals or athletes who need to eat more. The appetite stimulation is a feature, not a bug, for this population.
Strengths: Strong GH release, robust appetite stimulation, cheap. Weaknesses: Intense, sometimes uncontrollable hunger. Elevates cortisol significantly. Not suitable for anyone in a caloric deficit or with body composition goals.
Sermorelin — The Legacy Option
Best for: Users who want a GHRH analog with a longer regulatory track record. Sermorelin was the first GH secretagogue to receive FDA orphan drug designation.
Strengths: Longest clinical history, conservative choice, some clinics still prescribe it. Weaknesses: Very short half-life (~10 minutes) requiring precise timing. Lower GH output than CJC-1295. More expensive through clinical channels. Shows desensitization with continuous use.
Choosing Your Protocol
Decision Tree
“I don’t want to inject.” → MK-677 — oral, once daily. Accept the hunger and monitor glucose.
“I want the cleanest, most physiological GH boost.” → CJC-1295 + Ipamorelin — the gold standard. Requires 2–3 daily injections.
“I want maximum GH output and don’t care about side effects.” → CJC-1295 + GHRP-2 or GHRP-6 — stronger but dirtier.
“I want convenience AND quality.” → CJC-1295 + Ipamorelin on training days, MK-677 on rest days. Best of both worlds.
“I want the cheapest option.” → MK-677 at 10 mg/day — ~$30–60/month, oral, once daily.
“I want what my anti-aging clinic would prescribe.” → CJC-1295 + Ipamorelin or Sermorelin + Ipamorelin — the standard clinical protocols.
By Goal
| Goal | Best Protocol | Why |
|---|---|---|
| Anti-aging / longevity | CJC-1295 + Ipamorelin, pre-sleep | Clean GH pulse, promotes cellular repair during sleep |
| Body recomposition | CJC-1295 + Ipamorelin, 3x daily | Maximum pulsatile GH for fat oxidation and muscle protein synthesis |
| Sleep optimization | MK-677 10 mg OR CJC+Ipa pre-sleep | Both dramatically improve deep sleep and REM |
| Injury recovery | CJC-1295 + Ipamorelin + BPC-157 | GH accelerates tissue repair; add BPC-157 for targeted healing |
| Weight gain / appetite | MK-677 25 mg OR GHRP-6 | Both strongly stimulate appetite |
| Budget-conscious | MK-677 10 mg | Cheapest, easiest, no injection supplies |
| Competition prep | None — all banned by WADA | Every GH secretagogue is prohibited |
Cost Comparison
Estimated monthly cost based on standard dosing protocols (US pricing, research-grade sources):
| Protocol | Monthly Cost | Includes |
|---|---|---|
| MK-677 (10 mg/day) | $30–60 | Capsules or liquid only |
| MK-677 (25 mg/day) | $60–120 | Capsules or liquid only |
| CJC-1295 + Ipamorelin (2x daily) | $100–150 | Peptides + BAC water + syringes |
| CJC-1295 + Ipamorelin (3x daily) | $150–200 | Peptides + BAC water + syringes |
| CJC+Ipa + MK-677 hybrid | $130–180 | Injectable on training days, oral on rest days |
| HGH (2–4 IU/day) | $500–1,500 | Pharmaceutical-grade only |
What MK-677 Cannot Replace
A common question: “Why not just take MK-677 instead of injecting?”
MK-677 is genuinely excellent for sustained GH/IGF-1 elevation. But the CJC-1295 + Ipamorelin stack has specific advantages MK-677 cannot replicate:
-
Pulsatile GH release. Natural GH secretion occurs in pulses. CJC+Ipa mimics this pattern. MK-677 creates a sustained plateau. Pulsatile release may be more effective for fat oxidation and tissue repair because the body responds to the change in GH levels, not just the absolute level.
-
No insulin resistance. CJC+Ipa doesn’t worsen insulin sensitivity. MK-677 does over time. For anyone prediabetic or metabolically compromised, the injectable stack is safer long-term.
-
No hunger spike. If you’re cutting or maintaining body composition, MK-677’s appetite stimulation can be counterproductive. CJC+Ipa has minimal appetite impact.
-
Timing precision. With injectables, you control exactly when GH pulses occur — pre-sleep, post-workout, morning fasted. MK-677’s 24-hour half-life doesn’t allow this precision.
The trade-off is convenience. MK-677 wins on ease of use. CJC+Ipa wins on precision and metabolic safety. Many advanced users combine both.
Related Protocols
- CJC-1295 Protocol — full dosing, reconstitution, and cycle guide
- Ipamorelin Protocol — selectivity data, comparison to other GHRPs
- MK-677 Protocol — oral dosing, insulin management, long-term use
- Growth Hormone Stack — the CJC-1295 + Ipamorelin combination protocol
- Reconstitution Calculator — exact unit counts for your vials
Frequently Asked Questions
What is the best growth hormone peptide for beginners? +
MK-677 (Ibutamoren) is the easiest entry point — it's oral, once daily, and requires no reconstitution or injection. For those comfortable with injections, the CJC-1295 + Ipamorelin combination provides a more physiological GH release pattern with fewer metabolic side effects than MK-677.
Is CJC-1295 + Ipamorelin better than HGH? +
For most users, yes. CJC-1295 + Ipamorelin stimulates your own natural GH production in physiological pulses, preserving the body's feedback mechanisms. Exogenous HGH injects a flat dose that suppresses your natural production over time, costs 5–10x more, and carries a higher side effect burden. HGH is superior only for clinical GH deficiency or bodybuilding-level supraphysiological dosing.
Can I combine MK-677 with CJC-1295 and Ipamorelin? +
Yes, but strategically — not all three daily. The common approach is CJC-1295 + Ipamorelin on training days (pulsatile GH around workouts and sleep) and MK-677 on rest days (sustained baseline elevation). This provides 7-day-a-week GH support through complementary mechanisms.
Which GH peptide has the fewest side effects? +
Ipamorelin. It is the most selective growth hormone releasing peptide available — it does not raise cortisol, prolactin, or ACTH at standard doses. It has minimal appetite stimulation compared to GHRP-6, and no rapid desensitization like Hexarelin. The tradeoff is that it produces less raw GH output than more aggressive options.
How do GH peptides compare on cost? +
MK-677 is cheapest ($30–60/month). CJC-1295 + Ipamorelin costs $100–200/month depending on dosing frequency. GHRP-2 and GHRP-6 are similarly priced to Ipamorelin. Sermorelin is $150–300/month through clinics. All are dramatically cheaper than pharmaceutical HGH ($500–1,500/month).