GHRP-6 Dosage: Common Protocol, Study Dose and Calculator
GHRP-6 has no approved product to dose from. The doses published human studies used - a pharmacokinetic study and two stroke trials - and what is not established.
The short version
GHRP-6 has no FDA-approved product, so there is no approved dose. Community dosing guides most often describe 100-300 mcg by subcutaneous injection, 2 to 3 times daily on an empty stomach, for an 8-12 week cycle with a 4-week break. That is common practice, not trial-established. The published human studies I could verify gave it intravenously under medical supervision. One gave a single bolus of 100, 200 or 400 micrograms per kilogram to nine healthy men. Two gave 3.5 or 5 mg twice daily for 7 days to hospital patients with acute stroke, always with epidermal growth factor (EGF).
- Common practice is 100-300 mcg subcutaneous, 2-3 times daily, in an 8-12 week cycle with a 4-week break. It is not trial-established.
- Human dosing data: one pharmacokinetic study (single IV bolus of 100, 200 or 400 mcg/kg, 9 healthy men). Also two stroke trials (3.5 or 5 mg IV twice daily for 7 days, with EGF).
- The pharmacokinetic study measured how GHRP-6 moves through the bloodstream after one dose, not a treatment outcome.
- The only repeated human course I could verify is the stroke trials' 7 days in hospital. A longer twice-daily regimen exists only in an aged-rat study.
GHRP-6 has no approved dose, because it has no approved product. This page reports what published human studies and one animal study used, not a recommendation for what anyone should take. For legal status, FDA’s compounding safety flag and the WADA ban, see the main GHRP-6 guide.
US legal status - Research use only
GHRP-6 has no FDA-approved product and no approved dose. FDA lists it in Category 2 of its interim compounding-safety policy, and it is named explicitly in the WADA 2026 Prohibited List.
GHRP-6 dosage: the common protocol
Community dosing guides most often describe 100-300 mcg by subcutaneous injection, 2 to 3 times daily on an empty stomach, for an 8-12 week cycle with a 4-week break. This is common practice, not a dose any trial or regulator has established.
Common protocol
What is commonly used, not a dose established in trials. No regulator has set a dose for GHRP-6.
- Dose per administration
- 100-300 mcg
- How often
- 2 to 3 times daily, on an empty stomach, spaced at least 3-4 hours apart
- Route
- Subcutaneous injection
- Cycle length
- 8-12 weeks
- Break between cycles
- 4 weeks
- Common vial size
- 5 mg
- Timing
- Fasted - roughly 2-3 hours after a meal and 30-60 minutes before eating again - commonly morning, midday and before bed.
- Commonly paired with
- CJC-1295, Sermorelin
Guides describe starting at 100 mcg per injection and titrating up to 200-300 mcg over several weeks, and pairing with a GHRH analog (CJC-1295 no-DAC or sermorelin) in the same injection for a larger combined GH pulse.
Plan a cycle in the protocol builder or work out injection volume in the dosage calculator.
The common GHRP-6 dose is 100-300 mcg, 2 to 3 times daily, on an empty stomach, spaced at least 3-4 hours apart. From a 5 mg vial mixed with 2 mL of bacteriostatic water, 200 mcg is 8 units (0.08 mL) on a U-100 insulin syringe.
GHRP-6 5 mg vial: units per dose
Full 5 mg vial page: mixing, doses per vial, how long it lasts →
| Water added | Concentration | 1 unit = | 100 mcg | 200 mcg | 300 mcg |
|---|---|---|---|---|---|
| 1 mL | 5 mg/mL | 50 mcg | 2 units | 4 units | 6 units |
| 2 mL | 2.5 mg/mL | 25 mcg | 4 units | 8 units | 12 units |
| 3 mL | 1.67 mg/mL | 16.67 mcg | 6 units | 12 units | 18 units |
All GHRP-6 vial sizes: 2 mg · 5 mg · 10 mg
Units are on a standard U-100 insulin syringe (100 units = 1 mL), rounded to the nearest half unit - half-unit marks are on 0.3 mL syringes. Water volumes are examples: more water means more units per dose, not more doses per vial. For any other vial or dose, use the calculator below.
How many 5 mg vials a cycle takes
| Scenario | Dose | Doses a week | Weeks | Total | 5 mg vials |
|---|---|---|---|---|---|
| Low end of the common protocol | 100 mcg | 14 | 8 | 11.2 mg | 3 |
| High end of the common protocol | 300 mcg | 21 | 12 | 75.6 mg | 16 |
Whole vials, rounded up. Plan a cycle with your own numbers in the protocol builder. Keep mixed vials cold and use them within the window in how long reconstituted peptides last; where to inject: subcutaneous injection sites.
GHRP-6 doses used in human studies
Three published human studies I could verify report GHRP-6 doses. One is a pharmacokinetic study in healthy men. The other two are stroke trials in which GHRP-6 was given only with epidermal growth factor (EGF).
The pharmacokinetic study modelled GHRP-6’s disposition as a bi-exponential curve. Averaged across all three dose levels, it reported a distribution half-life of about 7.6 minutes and an elimination half-life of about 2.5 hours. The area under the concentration curve rose roughly in proportion to the dose.
This describes how GHRP-6 moves through and clears from the bloodstream after a single intravenous dose in nine men. It does not measure a training, recovery, muscle or appetite outcome at any dose.
The two stroke trials were both run by researchers at Cuba’s Center for Genetic Engineering and Biotechnology. They are the only published repeated human dosing I could verify. Patients started treatment in hospital within 12 hours of an acute ischaemic stroke.
- The open-label phase I-II trial reported the combination as safe, with better neurological and functional scores at 90 and 180 days (Hernández-Bernal 2024 - Hernández-Bernal F, Estenoz-García D, Gutiérrez-Ronquillo JH et al. Combination therapy of Epidermal Growth Factor and Growth Hormone-Releasing Hexapeptide in acute ischemic stroke: a phase I/II non-blinded, randomized clinical trial. Front Neurol. 2024;15:1303402., in the references below).
- The open-label phase III trial missed its primary endpoint. Disability, daily-living scores and survival did not differ from standard care overall. Benefit was reported only in subgroups, including 27 patients with severe stroke (Hernández-Bernal 2026 - Hernández-Bernal F, Subirós-Martínez N, Gutiérrez-Ronquillo JH et al. Phase III Open-Label, Randomized Clinical Trial of Epidermal Growth Factor and Growth Hormone Releasing Hexapeptide in Acute Ischemic Stroke. J Clin Neurosci. 2026;152:112195., in the references below).
GHRP-6 was never given alone in either trial. A 7-day course of intravenous doses in stroke patients is not a template for self-administered use.
Doses used in animal studies
An aged-rat study (Settembrini 1998 - Settembrini B, Figueroa J, Gallardo M et al. Growth Hormone (GH) but not IGF-I-Secretion is Stimulated in Aged Rats by Chronic Hexarelin and GHRP-6 administration. Endocr Regul. 1998;32(1):17-26., in the references below) first compared subcutaneous doses of 5, 10, 20, 40 and 80 mcg/kg body weight in young and aged rats. It found that 20 mcg/kg produced the maximal growth-hormone response. It then gave that dose subcutaneously, twice daily, for 15 or 30 days to young and aged rats. Both age groups still released GH in response to the peptide after 15 days of chronic treatment, though the response pattern changed by day 30.
What is not established
- No approved dose exists, for any population, indication, route or duration, because no product has completed FDA review.
- No repeated dosing schedule for self-administration has been studied in humans. The only repeated human course I could verify is the stroke trials’ 7 days of twice-daily intravenous doses, given in hospital and always with EGF. The other human study gave a single intravenous bolus to measure pharmacokinetics.
- No subcutaneous human dose has been published. The human studies used intravenous administration only, so the injection route sold to consumers has no published human dosing data behind it.
- The common protocol above comes from community dosing guides, not from any study, paper or regulator. It is current common practice, not a trial finding.
How to reconstitute GHRP-6
Turning a target amount into an injection volume depends on how a specific vial was reconstituted: how much diluent, and what resulting concentration. This page cannot know that for your vial. The dosage calculator walks through vial strength, diluent volume and target amount. It performs the math; it does not tell you what dose to use.
Who should not use it
No FDA-reviewed contraindication list exists, because GHRP-6 has never gone through that review. The pharmacokinetic study monitored nine healthy men for a matter of hours after a single IV dose. It establishes nothing about repeated self-administration outside that setting.
GHRP-6 is also reported to raise ACTH and cortisol alongside growth hormone, an effect distinct from newer, more selective secretagogues in the same class. That is a reason for caution for anyone with a pituitary or adrenal condition, pregnancy, or any diagnosed medical condition. For all of them, there is no regulator-reviewed basis for self-directed use.
GHRP-6 side effects and risks
FDA lists GHRP-6 in Category 2 of its interim compounding-safety policy, the category for nominated bulk substances where the agency identified potential significant safety risks. Beyond that flag:
- There is no long-term human safety study at any dose.
- There is no published human dosing schedule beyond the single-bolus pharmacokinetic study and the 7-day intravenous course in the stroke trials above.
- Material sold as a research chemical carries no regulator-verified purity, identity or concentration.
In the phase III stroke trial, severe adverse events occurred in 30 of 95 patients given EGF plus GHRP-6 and 18 of 93 on standard care. The investigators judged none to be treatment-related (Hernández-Bernal 2026 - Hernández-Bernal F, Subirós-Martínez N, Gutiérrez-Ronquillo JH et al. Phase III Open-Label, Randomized Clinical Trial of Epidermal Growth Factor and Growth Hormone Releasing Hexapeptide in Acute Ischemic Stroke. J Clin Neurosci. 2026;152:112195., in the references below). GHRP-6 is also prohibited at all times in sport under WADA section S2.2.4. See the main guide for that listing.
Related
- GHRP-6: what the research and regulatory record show
- GHRP-2 dosage: what the studies used
- Dosage calculator
Reconstitution arithmetic for a GHRP-6 vial: GHRP-6 dosage calculator.
GHRP-6 dosage calculator
Preset to a 5 mg vial and 100 mcg, the low end of the common protocol. Enter your own vial size, water and dose to get the syringe units to draw.
Your vial
Printed on the vial. There is no standard size - enter what yours says.
This changes how much you draw - never how many doses the vial holds.
100 units per mL. 1 unit = 0.01 mL. This is what almost every insulin syringe sold is, in every barrel size.
Capacity only. A 1 mL U-100 syringe holds 100 units - the scale decides that, not the barrel.
Draw this much
= 0.04 mL on a 1 mL U-100 syringe
- Concentration
- 2,500 mcg/mL
- Exact volume
- 0.04 mL
- Dose you actually get
- 100 mcg
- Doses per vial(unaffected by water volume)
- 50
Where to buy GHRP-6 for research
Each vendor is checked against my vendor checklist.
I don't list a vendor for GHRP-6 yet. Before buying from anyone, work through the vendor checklist.
Common questions
What is the usual GHRP-6 dose?
Community dosing guides most often describe 100-300 mcg by subcutaneous injection, 2 to 3 times a day on an empty stomach. They often start at 100 mcg and titrate up, paired with a GHRH analog like CJC-1295, for an 8-12 week cycle with a 4-week break. That is common practice, not a dose established by any human trial. The published human studies used monitored intravenous doses (see the next question).
What is the GHRP-6 dosage used in human studies?
Three published human studies I could verify report doses, all intravenous and supervised. A pharmacokinetic study gave nine healthy men a single bolus of 100, 200 or 400 micrograms per kilogram of body weight to measure how the peptide is absorbed and cleared. It found a distribution half-life of about 7.6 minutes and an elimination half-life of about 2.5 hours, averaged across the three dose levels. Two stroke trials gave hospital patients GHRP-6 at 3.5 or 5 mg twice daily for 7 days, always with 75 micrograms of epidermal growth factor (EGF). Neither isolates the effect of GHRP-6 alone.
Is there an FDA-approved GHRP-6 dose?
No. GHRP-6 has no FDA-approved product and no dose established as safe or effective by any regulator. The figures on this page are what studies gave their own participants under monitoring, not a recommendation.
What dose was used in animal studies?
An aged-rat study first found that 20 micrograms per kilogram by subcutaneous injection produced the maximal growth-hormone response. It then gave that dose twice daily for 15 or 30 days to young and aged rats. That is a rat dose in a chronic-treatment model, and there is no accepted method for converting it into a human dose.
What is the half-life of GHRP-6?
One pharmacokinetic study in nine healthy men reported a distribution half-life of about 7.6 minutes and an elimination half-life of about 2.5 hours. These were averaged across single intravenous doses of 100, 200 and 400 micrograms per kilogram. That is a single-dose IV profile in a small study, not a basis for any repeated-dosing schedule. The only repeated human course I could verify is 7 days of twice-daily intravenous doses in hospital stroke trials.
How do I work out reconstitution and injection volume?
That is arithmetic about a specific vial and diluent, not a dosing decision, and this page cannot know your vial. Use the dosage calculator to work out concentration and draw volume for whatever amount you are looking at. It does the math; it does not tell you what dose to use.
Who should not use GHRP-6?
No FDA-reviewed contraindication list exists, because GHRP-6 has never gone through that review. FDA has separately flagged GHRP-6 as a Category 2 compounding safety risk, and it is reported to raise ACTH and cortisol alongside growth hormone. That is a reason for caution for anyone with a pituitary or adrenal condition, pregnancy, or any diagnosed condition. For all of them, there is no regulator-reviewed basis for self-directed use.
When should I stop and get medical care?
Get emergency care (call 911 in the US) for a severe allergic reaction, chest pain, fainting, or any symptom that feels dangerous. Call Poison Control at 1-800-222-1222 if you have taken an unknown or excessive amount of anything sold as GHRP-6. This is not a substitute for a clinician who knows your history.
References (4 sources)
Bibliographic detail is fetched from PubMed, not written by me - so a citation here cannot drift from the paper it names. Study design comes from PubMed's own tags rather than my judgement.
- 1.Cabrales A, Gil J, Fernández E et al. Pharmacokinetic study of Growth Hormone-Releasing Peptide 6 (GHRP-6) in nine male healthy volunteers. Eur J Pharm Sci. 2013;48(1-2):40-6.Clinical trialPMID 23099431
- 2.Settembrini B, Figueroa J, Gallardo M et al. Growth Hormone (GH) but not IGF-I-Secretion is Stimulated in Aged Rats by Chronic Hexarelin and GHRP-6 administration. Endocr Regul. 1998;32(1):17-26.StudyPMID 10407366
- 3.Hernández-Bernal F, Estenoz-García D, Gutiérrez-Ronquillo JH et al. Combination therapy of Epidermal Growth Factor and Growth Hormone-Releasing Hexapeptide in acute ischemic stroke: a phase I/II non-blinded, randomized clinical trial. Front Neurol. 2024;15:1303402.StudyPMID 38638315full text
- 4.Hernández-Bernal F, Subirós-Martínez N, Gutiérrez-Ronquillo JH et al. Phase III Open-Label, Randomized Clinical Trial of Epidermal Growth Factor and Growth Hormone Releasing Hexapeptide in Acute Ischemic Stroke. J Clin Neurosci. 2026;152:112195.Randomised trialPMID 42462342