Overview
Overview
Ipamorelin is a synthetic pentapeptide that acts as a selective growth hormone secretagogue by mimicking ghrelin at the GH secretagogue receptor[1][2]. Its key advantage is high specificity for GH release without triggering ACTH or cortisol elevation, making it one of the safer GH secretagogues with minimal off-target hormonal effects[1][3]. This educational protocol presents a once-daily subcutaneous approach using practical dilution for precise insulin-syringe measurements. Reconstitute: Add
- Category
- Growth Hormone
- Routes
- subcutaneous
Mechanism
Ipamorelin
Mechanism of action
Mechanism of action
Ipamorelin works by pressing a specific 'release GH' button in the brain. That button is a receptor on the pituitary gland called GHS-R1a . It is the same receptor that the hunger hormone ghrelin uses. When ipamorelin binds to GHS-R1a, the pituitary releases a pulse of growth hormone. The pulse mimics the way your body already releases GH on its own. It does not flood the system with a constant supply, which is what direct GH injections do. Your body has a natural 'brake' on GH release. The brake is a hormone called somatostatin . Ipamorelin appears to ease that brake during a short window. This is one reason bedtime dosing is common — it lines up with a natural dip in somatostatin activity. Once GH is released, the liver converts most of it into IGF-1 . IGF-1 is the second signal that drives most of the effects people link to GH — muscle protein building, fat metabolism, and tissue repair. These effects stay under the body's normal feedback controls, so they scale with the GH pulse rather than running unchecked. The defining feature of ipamorelin is what it leaves alone. In lab studies by Raun et al. (1998), ipamorelin did not raise cortisol , ACTH , or prolactin even at doses many times higher than needed to release GH. Other GH-releasing peptides (GHRP-2 and GHRP-6) do raise these hormones. That clean profile is the main reason ipamorelin is often the first-choice GHRP in research protocols. Same receptor as ghrelin, located in the pituitary and hypothalamus. GH release is short and natural, peaking within ~30-40 minutes. Cortisol, ACTH, and prolactin stay flat at standard doses. Why dosing is built around clean pulses, not steady levels.
Key research findings
- 01
Synthetic pentapeptide that acts as an agonist at the ghrelin receptor (GHS-R1a) to stimulate GH release (pharmacology).
- 02
Characterized as the 'first selective' GH secretagogue: in preclinical work it released GH with little effect on ACTH/cortisol or prolactin, unlike the earlier GHRP-2/GHRP-6 (animal model; Raun et al., 1998, Eur J Endocrinol).
- 03
Greater selectivity for GH release than GHRP-2/GHRP-6 in comparative preclinical pharmacology (animal model / in vitro).
- 04
Short-acting, producing a discrete GH pulse; in research it is often paired conceptually with GHRH analogs on the rationale of complementary GH-axis stimulation (pharmacology).
- 05
Human data are limited and early-phase; most detailed characterization is preclinical, and no large long-term controlled human outcome trials are established.
Primary source: The core evidence is preclinical, notably Raun et al. (1998) establishing GH-release selectivity, with limited early-phase human pharmacology. Long-term controlled human outcome data are not established.
Pharmacokinetic profile
Single-dose plasma curve over 24h. Shaded band = commonly-cited therapeutic window. Illustrative only.
Researched Effects
Researched benefits
Areas of active research and investigation. Results may vary and are based on preclinical or early clinical data.
Supports increases in lean body mass and improvements in recovery through GH-mediated anabolic processes[1][2].
Enhances fat metabolism and supports favorable body composition changes over time[1].
Protocol Reference
Protocol reference
Commonly cited research range: 200–300 mcg, daily.
Reference figures reported in the research literature — not a dosing recommendation. For interactive vial math and scheduling, see the Calculator and Schedule tabs.
Cited protocol & reconstitution guide
Source-backed reference fields by phase, including any volume fields authored in the cited guide.
Week 1 (Assessment)
100 mcg/day
Weeks 2–3 (Titration)
200 mcg/day
Weeks 4–8 (Standard)
200–300 mcg/day
Weeks 9–12 (Extended)
200–300 mcg/day
Off-cycle (4 weeks)
0 mcg
Women's dosing context
100–200 mcg per shot
| Phase | Reference amount | Units / volume |
|---|---|---|
| Week 1 (Assessment) | 100 mcg/day | 4 units (0.04 mL) |
| Weeks 2–3 (Titration) | 200 mcg/day | 8 units (0.08 mL) |
| Weeks 4–8 (Standard) | 200–300 mcg/day | 8–12 units (0.08–0.12 mL) |
| Weeks 9–12 (Extended) | 200–300 mcg/day | 8–12 units (0.08–0.12 mL) |
| Off-cycle (4 weeks) | 0 mcg | 0 units (0.00 mL) |
| Women's dosing context | 100–200 mcg per shot | 4–8 units (0.04–0.08 mL) |
Titration protocol
- Week 1Start100 mcg/day
1x at bedtime, fasted — inject on an empty stomach, typically 1–2 hours after a meal and 20–30 minutes before eating again.
- Weeks 2–3Build200 mcg/day
1x at bedtime, or split 100 mcg AM + 100 mcg PM; keep empty-stomach timing (1–2 hours after a meal, 20–30 minutes before eating again).
- Weeks 4–8Build200–300 mcg/day
1–2x daily; AM fasted + bedtime is the common split.
- Weeks 9–12Build200–300 mcg/day
Continue if tolerated; some protocols run to week 16. Three shots per day is the community maximum, with the third shot often timed post-workout. Do not double doses after a miss — resume at the next scheduled time.
- Off-cycle (4 weeks)Build0 mcg
Resting period before starting a new cycle.
- Not specified (women's dosing context)Maintenance100–200 mcg per shot
Community protocols often use the lower end of the dose range for women, with the bedtime shot prioritized; not a formal guideline.
Storage & Handling
Storage requirements(typical for most peptides)
Can be stored for extended periods. Protect from moisture.
Store in refrigerator door. Never freeze after reconstitution.
Label vials with reconstitution date. Discard if cloudy.
Reconstitution steps
- 01🌡️Bring the vial to room temperature — let the ipamorelin vial sit out for 5–10 minutes before mixing.
- 02🧴Swab both stoppers — wipe the rubber tops of the peptide vial and the BAC water vial with separate alcohol swabs.
- 03💉Draw 2 mL bacteriostatic water into a sterile syringe — this 5 mg vial yields 2.5 mg/mL.
- 04💧Add water slowly — insert the needle into the peptide vial and let the water drip slowly down the inside glass wall; do not blast it directly onto the powder.
- 05🔄Swirl gently — roll or swirl the vial between your fingers until the powder fully dissolves; do not shake.
- 06🏷️Check the solution — it should be clear and colorless with no floating particles.
- 07❄️Label and store — write the concentration (2,500 mcg/mL) and date on the vial; refrigerate at 2–8 °C and use within about 28 days.
- 08💉Important: This content is intended for research and educational purposes only and does not constitute medical advice, diagnosis, or treatment.
Additional storage notes
Store at 2–8 °C (35.6–46.4 °F) for short-term or −20 °C (−4 °F) for long-term storage in dry, dark conditions [10] [11] .
Refrigerate at 2–8 °C (35.6–46.4 °F); use within ~4 weeks with bacteriostatic water [12] . For longer storage, freeze aliquots at −20 °C (−4 °F) and avoid repeated freeze–thaw cycles [11] .
Allow vials to reach room temperature before opening to reduce condensation uptake [10] .
Clinical Evidence
Clinical evidence
Research demonstrates effective GH stimulation without cortisol elevation. Improves body composition, sleep quality, and recovery.
The core evidence is preclinical, notably Raun et al. (1998) establishing GH-release selectivity, with limited early-phase human pharmacology. Long-term controlled human outcome data are not established.
- 01Synthetic pentapeptide that acts as an agonist at the ghrelin receptor (GHS-R1a) to stimulate GH release (pharmacology).
- 02Characterized as the 'first selective' GH secretagogue: in preclinical work it released GH with little effect on ACTH/cortisol or prolactin, unlike the earlier GHRP-2/GHRP-6 (animal model; Raun et al., 1998, Eur J Endocrinol).
- 03Greater selectivity for GH release than GHRP-2/GHRP-6 in comparative preclinical pharmacology (animal model / in vitro).
- 04Short-acting, producing a discrete GH pulse; in research it is often paired conceptually with GHRH analogs on the rationale of complementary GH-axis stimulation (pharmacology).
- 05Human data are limited and early-phase; most detailed characterization is preclinical, and no large long-term controlled human outcome trials are established.
Evidence maturity varies by compound; much peptide research is preclinical (in vitro or animal-model). Where human data are limited, findings should be read as research observations, not clinical conclusions.
References
Literature references
Published research articles and sources related to Ipamorelin.
- 01Translational Andrology and Urology (PMC) — Beyond the androgen receptor: the role of growth hormone secretagogues in the modern management of body composition in hypogonadal males (2020 review) View Sourceet al. (2020)
- 02European Journal of Endocrinology (PubMed) — Ipamorelin, the first selective growth hormone secretagogue (1998 preclinical pharmacology study) View Sourceet al. (1998)
- 03European Journal of Anatomy — Chronic in vivo Ipamorelin treatment stimulates body weight gain and growth hormone (GH) release in vitro in young female rats (2002 animal study on chronic dosing) View Sourceet al. (2002)
- 04Pharmaceutical Research (PubMed) — Pharmacokinetic-pharmacodynamic modeling of ipamorelin, a growth hormone releasing peptide, in human volunteers (1999 Phase I clinical pharmacology study) View Sourceet al. (1999)
- 05European Journal of Anatomy — Three-week chronic in vivo ipamorelin treatment: no desensitization of GH release mechanisms (2002 animal study) View Sourceet al. (2002)
- 06International Journal of Colorectal Disease (PubMed) — Prospective, randomized, controlled, proof-of-concept study of the ghrelin mimetic ipamorelin for the management of postoperative ileus in bowel resection patients (2014 Phase II clinical trial) View Sourceet al. (2014)
- 07Johns Hopkins Arthritis Center — How to Give a Subcutaneous Injection (patient educational resource) View Source
- 08NCBI Bookshelf — Best practices for injection: asepsis, preparation, and administration techniques View Source
- 09Pharmacologic Considerations (PMC) — Subcutaneous drug injection: review of pharmacologic considerations and site rotation practices View Source
- 10NIBSC (National Institute for Biological Standards) — Peptide Handling, Dissolution & Storage Guidelines (peptide storage recommendations) View Source
- 11Bachem (Peptide Manufacturer) — Handling and Storage Guidelines for Peptides (technical best-practices) View Source
- 12Creative Peptides — How Long Do Peptides Last? Peptide Stability & Shelf Life (technical article on peptide stability) View Source
- 13Pure Lab Peptides — Ipamorelin 5 mg product page (quality and batch documentation) View Source
Observed Effects
Observed effects in cited research
Commonly reported (mild)
- Mild headache, usually short-lived.
- Light water retention or bloating.
- Mild appetite increase. Ipamorelin is less appetite-driving than GHRP-6.
- Tingling in hands or feet, mostly at the start of a cycle.
Reported with higher doses or longer use
- Mild joint stiffness.
- Temporary fatigue.
- Carpal tunnel-style symptoms (linked to GH-related fluid retention).
Injection-site reactions
- Some users report mild redness, stinging, or a small bump at the injection site. Rotating sites and keeping sterile technique reduces how often this happens.
What ipamorelin does not raise
- Unlike GHRP-2 and GHRP-6, ipamorelin did not raise cortisol (a stress hormone), ACTH , or prolactin in lab testing at standard GH-releasing doses (Raun et al. 1998). That cleaner profile is the main reason it is generally better tolerated than the other GHRPs.
Clinical tolerability data
- In the Beck et al. 2014 Phase II trial (117 bowel surgery patients, NCT00672074), ipamorelin given as 0.03 mg/kg IV twice daily for up to 7 days produced treatment-related adverse event rates similar to placebo. The trial did not meet its efficacy endpoint, but tolerability was not the reason the program was discontinued.
Research Considerations
Research considerations
Research peptide. May affect blood sugar. Consult healthcare provider.
- Active or recent cancer. GH and IGF-1 can support cell growth. Anyone with current or recent cancer should avoid GH-raising compounds.
- Uncontrolled blood sugar disease (type 1 or type 2 diabetes). GH affects insulin sensitivity. Glucose control can shift.
- Severe heart disease. GH can cause fluid retention. That can stress an already weak heart.
- Pregnancy or breastfeeding. There is no safety data for ipamorelin in either group.
- Children or teens. GH and IGF-1 directly affect growth plates. Ipamorelin is not for anyone still growing.
- Competitive athletes. Ipamorelin and all ghrelin mimetics are banned under WADA rules.
- You have a strong family history of cancer.
- You are pre-diabetic or have a fasting glucose near the high end of normal.
- You take medications that affect blood sugar (insulin, GLP-1s, steroids).
- You have sleep apnea — GH can worsen it.
- You have carpal tunnel symptoms — GH-related fluid retention can flare them.
Factors noted in the research literature; not patient-specific medical advice.
Regulatory Status
Regulatory status
RUO
Comparisons
Comparisons
| Compound | Mechanism | Route | Status |
|---|---|---|---|
| Ipamorelinthis | Binds to ghrelin receptors to stimulate pituitary gland to release growth hormone. Highly selective with minimal side effects. | subcutaneous | Investigational / RUO |
| Sermorelin | Binds to GHRH receptors to stimulate pulsatile GH release, mimicking natural patterns. Preserves feedback mechanisms. | subcutaneous | Investigational / RUO |
| Tesamorelin | Binds to GHRH receptors to stimulate endogenous GH production. Preferentially reduces abdominal fat accumulation. | subcutaneous | Investigational / RUO |
| CJC-1295 | Binds to GHRH receptors to stimulate GH release. Modified structure provides extended duration of action (up to 7 days). | subcutaneous | Investigational / RUO |
| CJC-1295 DAC | A synthetic GHRH analog with a drug-affinity-complex (DAC) modification that binds serum albumin, greatly extending half-life and producing sustained stimulation of pituitary GH release. | subcutaneous | Investigational / RUO |
| Kisspeptin | A neuroendocrine peptide that activates KISS1R (GPR54) on GnRH neurons to stimulate gonadotropin-releasing hormone secretion, a key upstream regulator of the reproductive axis. | subcutaneous | Investigational / RUO |
| KPV | A C-terminal tripeptide fragment of alpha-melanocyte-stimulating hormone (Lys-Pro-Val) studied for anti-inflammatory activity, proposed to act through intracellular pathways (e.g., NF-kB modulation) without melanocortin pigmentary activity. | subcutaneous | Investigational / RUO |
Attributes shown for research comparison only; not a statement of efficacy or therapeutic equivalence.
FAQ
Frequently asked questions
Ipamorelin is a research peptide that signals the pituitary to release the body's own growth hormone in natural pulses. It is also called NNC 26-0161. It is the most selective member of the GHRP family — it raises GH without raising cortisol, prolactin, or other stress hormones.
The common starting dose in community protocols is 100 mcg per shot, once daily at bedtime, on an empty stomach, for about one week. Most protocols then step up to 200 mcg per shot. For custom vial math, use the Pep Pal calculator .
For a 2 mg vial with 1.0 mL BAC water: 200 mcg = 10 units. For a 5 mg vial with 2.0 mL BAC water: 200 mcg = 8 units. For a 10 mg vial with 3.0 mL BAC water: 200 mcg = 6 units. Units are based on a standard U-100 insulin syringe. See the full reconstitution table on this page.
Common setups are 1.0 mL BAC water for a 2 mg vial, 2.0 mL BAC water for a 5 mg vial, and 3.0 mL BAC water for a 10 mg vial. Drip the BAC water down the inside wall of the vial. Swirl gently — do not shake. Refrigerate and use within about 28 days.
Ipamorelin has a terminal plasma half-life of about 2 hours in human pharmacokinetic data (Gobburu et al. 1999). GH peaks around 30-40 minutes after the shot and returns to baseline within 2-3 hours.
No. Ipamorelin is not FDA-approved for any human use. It reached Phase II clinical trials for postoperative ileus (a gut-recovery condition) and was discontinued after the trial did not show efficacy. Ipamorelin was on the FDA's Category 2 503A compounding list from September 2023 to September 2024, then removed after the nominator withdrew. As of June 2026 it is not Category 1 and is not eligible for 503A compounding. It is also banned under WADA anti-doping rules.
Research-community protocols often use 100-200 mcg per shot for women, with the bedtime shot prioritized. The lower end of the dose range is cited for body-size and baseline GH-response reasons. No clinical trial has set a sex-specific dose for ipamorelin. This is not a personal medical recommendation.
A common beginner schedule is 100 mcg per shot, one shot per day at bedtime, on an empty stomach, for one week. Most protocols then move to 200 mcg per shot in week 2. By week 4, the most common range is 200-300 mcg per shot, one or two times daily. Cycles run 8-12 weeks on, 4 weeks off.
A frequently cited stack uses 100 mcg CJC-1295 (no DAC, also called Mod GRF 1-29) plus 200 mcg ipamorelin together in a single subcutaneous shot at bedtime. The two peptides press different receptors, so the GH pulse is larger than either one alone. See the CJC-1295 + Ipamorelin stack guide for the full protocol.
Most community protocols run 8 to 12 weeks on, then 4 weeks off. Some clinician-guided protocols extend the on-period to week 16. The off-period is intended to keep the GH receptor responsive.
Most research protocols cap single shots around 300 mcg because GH release flattens out beyond that point — more dose does not equal more GH pulse. Daily totals up to 900 mcg (300 mcg three times per day) have been used in community protocols, but tolerability and observed effect risk climb at the high end.
The most commonly reported effects are mild headache, light water retention, mild appetite increase, and tingling in the hands or feet. Most fade within the first 1-2 weeks. Unlike GHRP-2 and GHRP-6, ipamorelin did not raise cortisol or prolactin in clinical testing at standard doses.
Ipamorelin and CJC-1295 are not interchangeable. They work on different receptors. Ipamorelin presses the GHS-R1a (ghrelin) receptor. CJC-1295 presses the GHRH receptor. They are most often used together because pressing both receptors at once produces a larger GH pulse than either one alone.
Store reconstituted ipamorelin at 36-46F (2-8C), protected from light, and use within about 28 days. Avoid repeated freeze-thaw cycles unless freezing in single-use aliquots.
Use the Pep Pal reconstitution calculator to convert vial size, BAC water volume, and target dose into exact syringe units.
Research-use notice
Research Use Only. This educational content and calculation support is intended for private research documentation. It does not provide medical advice, human-use directions, or claims of safety or effectiveness.