CJC-1295 vs Ipamorelin: Benefits, Risks and Dosage

CJC-1295 and ipamorelin are the two growth hormone peptides most often named in the same breath, and most often sold in the same vial. Each one gets the pituitary to put out more growth hormone of the body’s own making. They do it through different receptors, on different timetables, with different records behind them, which is why the question of one against the other keeps coming up.

Simms Research sells Ipamorelin on its own, a single 10mg vial at $74, and the pair as CJC-1295 noDAC / Ipamorelin, a 10mg vial holding 5mg of each, at $78. For most buyers the real choice sits between those two vials.

What is CJC-1295?

CJC-1295 is a synthetic version of growth hormone-releasing hormone (GHRH), the signal the brain sends down to the pituitary to start growth hormone release. It keeps the 29 amino acids at the front of the natural hormone, the part responsible for its full effect, and replaces four of them so that blood enzymes can’t cut the chain apart within minutes. The Montreal company ConjuChem built it in the early 2000s.

The name covers two forms. ConjuChem’s original adds a Drug Affinity Complex, or DAC, a chemical hook that latches onto albumin so the peptide stays active for about a week. The form in almost every blend, Simms Research’s included, has no DAC, is also sold as Mod GRF 1-29, and is gone in about 30 minutes. The blend’s dosage guide covers how the two forms are dosed. Sermorelin is the same 29-amino-acid chain with none of the swaps; Sermorelin vs Ipamorelin covers how it compares.

The human data come from two 2006 trials in healthy adults, run on the DAC form. A single injection kept average growth hormone between two and ten times its starting level for at least six days, and IGF-1, the growth factor the liver makes in response, up to three times higher for over a week.

What is ipamorelin?

Ipamorelin is a five-amino-acid peptide that copies ghrelin, the hunger hormone released by the stomach, at its pituitary receptor, known as GHS-R1a. Novo Nordisk made it in the 1990s by trimming down GHRP-1, one of the older growth hormone-releasing peptides.

Its selling point is how little else it touches. In its 1998 debut paper, ipamorelin released about as much growth hormone in pigs as GHRP-6, while GHRP-2 and GHRP-6 each raised ACTH and cortisol and ipamorelin didn’t, even at doses 200 times above the one that worked. FSH, LH, prolactin and TSH held steady too. In healthy men tested at five dose levels, every dose produced one growth hormone burst, highest around the 40-minute mark and gone within hours, and the peptide’s half-life was two hours.

Difference between CJC-1295 and ipamorelin

They pull different levers on the same cells. CJC-1295 works the GHRH receptor, which drives how much growth hormone the pituitary makes as well as releases; in mice, daily CJC-1295 raised growth hormone gene activity in the gland itself. Ipamorelin works the ghrelin receptor, which sets off release of what is stored as one sharp pulse.

Timing is the second difference. Without DAC, CJC-1295 lasts about half an hour and ipamorelin a couple of hours, so both give a pulse and both are injected once to three times daily. With DAC, CJC-1295 stops being a pulse and becomes a week-long background signal.

CJC-1295 vs ipamorelin side by side

Line by line, down to the Simms Research vials:

Why CJC-1295 and ipamorelin are taken together

Because the two signals multiply rather than add. In a 2001 study in healthy men, Kyoto researchers gave low doses of ghrelin, the hormone ipamorelin copies, alone, GHRH alone, and the two together. The combined response beat the sum of the two separate ones, while ACTH and prolactin showed no such boost. The effect had first been shown with GHRP-6 and GHRH in 18 men in 1990.

The ghrelin side also leans on the GHRH side. In a 1998 University of Michigan study, nine young men were given GHRP-6 after a drug that blocked their own GHRH. Their growth hormone peak fell from 33.8 to 6.2 micrograms per liter, about four-fifths of the response gone. A ghrelin-type peptide on its own still depends on whatever GHRH the body happens to be sending; CJC-1295 makes sure that signal is there.

No trial has tested CJC-1295 and ipamorelin as a pair. The case rests on these studies of their parent hormones and on timing: the no-DAC form and ipamorelin are both short-acting, so they work best landing at the same moment, which one vial guarantees.

Ipamorelin with or without CJC-1295

Ipamorelin works without CJC-1295; CJC-1295 makes each of its pulses larger. Whether the second peptide earns its place comes down to what changes in the vial and what it costs.

Simms Research’s blend holds 5mg of each peptide, so it carries half the ipamorelin of the plain 10mg vial, and every dose is counted per peptide. The standard injection is 100mcg of both together, 200mcg of powder in a single draw, and the vial holds 50 of them.

Drawn to the last drop, the blend’s 100mcg-of-each injection costs $1.56 and a 100mcg draw of plain ipamorelin $0.74. The calendar usually ends a vial first, though: mixed, either one keeps 28 days, so a once-nightly schedule retires the vial on day 28 with draws still in it. Over 30 days, plain ipamorelin at 200mcg costs $79 once nightly and $89 twice a day; the blend costs $84 once nightly and $94 twice a day. On the same schedule, CJC-1295 adds about $5 a month.

Plain ipamorelin is the better buy when the research wants its clean pulse and nothing else, when ipamorelin is paired with tesamorelin or sermorelin drawn from their own vials, or when the protocol calls for 200 to 300mcg of ipamorelin per injection, since raising the draw on the blend raises the CJC-1295 with it. The blend is the better buy when the research wants both signals in every injection from one vial and one draw.

CJC-1295 vs ipamorelin dosage

Both go in up to three times a day, bedtime first. What differs is the water and what a unit holds, so units never carry over from one vial to the other:

The full schedules, timing around meals and sleep, and cycle lengths are in the ipamorelin dosage chart and the blend’s own dosage guide. For the blend, the peptide calculator gives the right units only when the vial size is entered as 5mg, the amount of each peptide. Research Water, $20 for 10mL, is enough for three plain ipamorelin mixes or four blend mixes, and the peptide storage guide covers how long a mixed vial keeps.

CJC-1295 vs ipamorelin for muscle growth

Neither has a muscle or strength trial in healthy adults. What both move is growth hormone and IGF-1, the pair moves growth hormone further than either alone, and CJC-1295 is the one with IGF-1 measured in people.

Growth hormone itself shows what that buys. In a 2008 Stanford review of trials in young, fit adults, 303 of them on injected growth hormone, lean body mass rose 2.1kg against controls, a measure that counts water as well as muscle, while strength and exercise capacity did not improve. Fluid swelling and fatigue came more often. In a companion review in older adults, lean mass rose the same 2.1kg while fat fell 2.1kg, with body weight unchanged.

Do CJC-1295 and ipamorelin make muscles stronger? Nothing in the research shows it. They are studied for body composition, more lean mass and less fat, and the strongest growth hormone rise among these peptides comes from pairing a GHRH-type with a ghrelin-type, which is what the blend does. The blend guide’s training-day protocols add an injection after training.

Does CJC-1295 raise testosterone?

No. CJC-1295 and ipamorelin work the growth hormone axis, and testosterone runs on another: LH from the pituitary tells the testes to make it. In the 1990 study of 18 men, GHRH and the ghrelin-type peptide, given alone and together, left LH where it was over the following hour. Ipamorelin left LH and FSH flat in Novo Nordisk’s pig tests.

Set against testosterone itself, the difference is direct against indirect. Testosterone acts on muscle through androgen receptors; these peptides reach it only through growth hormone and IGF-1. A 2020 Baylor review of growth hormone peptides in men with low testosterone treated them as an add-on for fat gain and muscle loss, used alongside testosterone rather than in its place.

Downsides of CJC-1295 and ipamorelin

Both are mild at protocol doses. What people notice first after the blend is a warm flush across the face, over within minutes, and it belongs to the GHRH side: in the 1990 study, 16 of 18 men flushed after GHRH, for one to three minutes.

CJC-1295’s downsides depend on the form. The DAC form keeps its pulses but lifts the growth hormone level between them 7.5-fold for a week, a pattern the body never makes by itself, and its 2006 trials gathered their headaches, diarrhea and flushing at the top doses, with no serious reactions. The no-DAC form keeps to the body’s own rhythm but needs one to three injections a day, and in a blend its dose is tied one to one to ipamorelin’s.

Ipamorelin’s main downside is a little hunger within an hour of a dose. Its largest trial gave 117 adults recovering from bowel surgery far larger doses, twice daily for as long as seven days, and adverse events came in 87.5% of them against 94.8% on placebo, most from the operation itself. With either peptide, the extra growth hormone can bring light water retention and tingling hands in the first weeks.

Which is better, CJC-1295 or ipamorelin?

For the largest growth hormone response per injection, the two together. For the cleanest single signal at the lowest cost, ipamorelin alone.

Choose the blend when the research is after the strongest pulse these peptides can produce. Two receptors on the same cells, a synergy shown in people with their parent hormones, and both signals in one 5-unit draw, at $84 a month on one nightly injection.

Choose plain ipamorelin when the research wants a growth hormone pulse with nothing else moving: no cortisol, no prolactin, no flush. It costs $79 to $89 a month, leaves the dose free to rise to 300mcg, and pairs with tesamorelin or sermorelin from their own vials. Tesamorelin vs Ipamorelin covers where ipamorelin and the blend stand against tesamorelin.

CJC-1295 on its own makes sense mainly in its weekly DAC form, the one its human trials used. The no-DAC form is built to be paired, which is why Simms Research sells it inside the blend.

How the CJC-1295 and ipamorelin vials tested

Both vials measured slightly above the label. An independent ISO-certified lab tested the current blend batch in May 2026: CJC-1295 came to 5.33mg and ipamorelin to 5.28mg, purity was 99.93%, mass spectrometry confirmed both peptides and two endotoxin runs passed. For a blend that split is the number to check, and here the two sit within a twentieth of a milligram of each other.

The current plain ipamorelin batch, tested in July 2026, averaged 10.32mg across three vials, 10.12 to 10.44mg, at 99.77% purity, and cleared endotoxin, heavy-metal and sterility screens. The batch before it measured 10.29mg at 99.92%. The certificates open from the blend’s lab page and the ipamorelin page, alongside every published certificate, and the COA reading guide walks through each figure.

Frequently asked questions

Is CJC-1295 / ipamorelin taken 5 or 7 days a week?

Both are used. Five days on and two off is the usual pattern: at two injections a day that is 1mg of CJC-1295 and 1mg of ipamorelin weekly, against 1.4mg of each on seven days. The blend’s dosage guide covers how long a run lasts.

What is the strongest growth hormone peptide?

For raw release, a GHRH-type paired with a ghrelin-type. For a measured result, tesamorelin, the one with large trials behind it, on abdominal fat; Sermorelin vs Tesamorelin covers that evidence.