CJC-1295 and ipamorelin dosage: what the human studies actually gave

There is no tested daily dose of CJC-1295, of ipamorelin, or of the two together, and no human dose of either has been established. Below is the record of what the human studies of CJC-1295 and ipamorelin gave, by what route and how often, why the daily schedules sold online do not follow from it, and the unit arithmetic that confuses people most. Nothing here is a recommendation; a prescriber sets a dose, and for these two peptides there is no approved product to prescribe. Neither is FDA-approved, and products labeled “for research use only” are not legal to use on people.

What the human studies gave

Doses were set per kilogram of body weight in monitored research settings. The last column shows what that works out to for a 70 kg adult, for scale only.

Two notes on the units. mcg/kg is micrograms per kilogram of body weight; 1 mg is 1,000 mcg. The 1999 ipamorelin paper reported doses in nmol/kg (nanomoles per kilogram); the mcg/kg figures above convert them using ipamorelin’s molecular weight of 711.9.

In the 2006 CJC-1295 study, the authors concluded the drug was “relatively well tolerated, particularly at doses of 30 or 60 microg/kg.” At 125 and 250 mcg/kg, flushing, diarrhea and longer-lasting injection site reactions were more common. That is the clearest thing these studies say about going higher: the hormone response kept rising, and so did the side effects.

What happened over time in the studies

The two CJC-1295 studies tracked hormone levels after a single injection and after repeats. One injection raised growth hormone 2- to 10-fold for 6 days or more, and IGF-1 (insulin-like growth factor 1, the hormone the liver makes in response) 1.5- to 3-fold for 9 to 11 days. With repeated injections, IGF-1 stayed above baseline for up to 28 days, meaning each dose landed before the last had cleared. A week after one dose, the body’s own growth hormone pulses were still intact.

Ipamorelin behaved in the opposite way. A single infusion produced one burst of growth hormone, peaking at about 40 minutes and gone within 6 hours at every dose. FDA’s review notes that prolonged exposure to the peptide may not keep growth hormone release going, and raises the concern that someone with partial growth hormone deficiency could lose the response over time as their stores run down.

Neither drug has human data past the study windows above. Nothing tells you what month three looks like, which is also why there is no sensible answer to questions about cycling, stacking or what to do after a missed injection.

Why the online “per day” protocols are not validated

Clinic menus and forums usually describe CJC-1295 without DAC plus ipamorelin injected under the skin every day for weeks or months. Those protocols do not come from the studies above, for five reasons.

1. The tested CJC-1295 was a weekly drug. The DAC version binds to albumin and has a half-life of about 6 to 8 days. One injection raised growth hormone for 6 days or more and IGF-1 for 9 to 11 days, and repeat doses stacked up. The study authors wrote that “a minimum dosing interval of 7 d appears reasonable.” Daily dosing of the DAC version was never tested and, given the stacking, would expose a person to far more than any study did.
2. The version without DAC has no published human dosing study. Without the albumin linker it lacks the feature that gave the DAC version its week-long half-life, and its own half-life in people has not been published. Any daily dose for it is a guess.
3. Ipamorelin was tested intravenously, in hospital. Both published human studies infused it into a vein, under medical supervision. We found no published trial of ipamorelin injected under the skin, so nobody has measured how much is absorbed that way or what a daily injection does over time. FDA has said it has not identified safety information for other injection routes.
4. The combination was never tested. No published study gave CJC-1295 and ipamorelin together, measured the combined hormone response, or checked its safety.
5. The outcomes were hormone levels. The CJC-1295 studies measured growth hormone and IGF-1 in healthy adults. The ipamorelin trials measured bowel recovery after surgery and found no significant benefit. None measured muscle, fat, sleep or recovery from training, the reasons people use these peptides.

FDA’s advisory committee reviewed exactly this evidence in 2024. It voted against adding ipamorelin (0 yes, 12 no, 1 abstain) and every form of CJC-1295 (no more than 1 yes vote out of 13) to the list of substances pharmacies may compound.

The syringe arithmetic

These peptides are sold as freeze-dried powder that has to be mixed with bacteriostatic water (see how to reconstitute and bacteriostatic water). The unit marks on a U-100 insulin syringe measure volume, not peptide: 100 units is 1 mL, so 1 unit is 0.01 mL. The concentration in the vial decides how much peptide each unit holds.

A worked example with a 2 mg vial:

• 2 mg = 2,000 mcg. That is the total in the vial no matter how much water is added.
• Add 2 mL of water: 2,000 mcg divided by 2 mL = 1,000 mcg per mL.
• 1,000 mcg per mL divided by 100 units = 10 mcg per unit.
• So 100 mcg is 10 units, 200 mcg is 20 units and 300 mcg is 30 units.

The same arithmetic at two example vial sizes:

Blended vials. Some vials contain both peptides. Every unit drawn from them contains some of each, in the ratio the label claims. For a vial labeled 5 mg of each peptide mixed with 2 mL of water, every unit holds 25 mcg of CJC-1295 and 25 mcg of ipamorelin. There is no way to change one without the other, and the arithmetic has to be done for each peptide separately.

The table describes arithmetic, not a dose. The reconstitution calculator below does the same math for any vial and any volume of water, and the mg/mL to units converter works the other way round.

Five errors turn up over and over in questions about these two peptides:

• Confusing the two CJC-1295 versions. A schedule written for one does not apply to the other. The DAC version lasts about a week; the version without DAC does not, and has no published human data.
• Confusing mg and mcg. 1 mg is 1,000 mcg. The study doses were per kilogram, so a 30 mcg/kg dose works out in milligrams, not micrograms, for an adult.
• Treating units as micrograms. A unit is a hundredth of a millilitre. It holds whatever the concentration says.
• Forgetting that the water changes everything. A chart made for 1 mL of water is wrong for a vial mixed with 2 mL.
• Trusting the number on the label. Research-grade vials carry no FDA-verified content, purity or sterility, so any arithmetic rests on an unverified figure. The guide to reading a certificate of analysis explains what a certificate can and cannot show.

Not approved, not legal to use on people

Neither CJC-1295 nor ipamorelin is an FDA-approved drug, so neither has a label, a labeled dose or a lawful route to compounding under section 503A. Vials labeled “for research use only” fall under 21 CFR 312.160, which allows shipment only for tests in laboratory animals or in vitro, with a label reading “Not for use in humans.” Using them on a person is outside that rule.

The October 2026 news does not change this. As of November 2, 2026, HHS says it does not intend to take enforcement action over 503A compounding of six named peptides, when each is compounded as a single ingredient and other conditions are met. CJC-1295 and ipamorelin are not among the six, and a two-peptide vial would fall outside the policy regardless.

If raising growth hormone is the point, the only drug in this family with a labeled dose is tesamorelin, and ipamorelin vs tesamorelin sets the two side by side. The ipamorelin guide covers its side effects and status in detail, and the FDA status tracker keeps the dated record for both.