Quick answer: no study has measured CJC-1295 and ipamorelin side effects as a pair. Taken alone, the long-acting DAC form of CJC-1295 caused injection-site reactions in about 70% of healthy adults, headache in 63%, diarrhea in 43% and flushing with a short blood pressure drop in 30%.[1] Ipamorelin, given by IV after bowel surgery, was linked to more low potassium (12.5% vs 3.4%), insomnia and high blood sugar than placebo.[2] The no-DAC CJC-1295 usually sold with ipamorelin has no human safety data.[5]
This guide covers what each study found, FDA’s safety concerns, what raising growth hormone can do, and who should be cautious. For background, see our CJC-1295 and ipamorelin guide and the growth hormone peptides hub.
Where the safety data come from
- CJC-1295 with DAC: three studies in 63 healthy adults, most of whom got a single injection under the skin.[1]
- Ipamorelin: one published phase 2 trial in 114 hospital patients, given by IV for up to 7 days after bowel surgery.[4]
- CJC-1295 without DAC: none. FDA found no safety or pharmacology studies, and a 2026 review found no peer-reviewed human studies.[1][5]
- The combination: none. The 2026 review called the pairing anecdotal, without controlled clinical evidence.[5]
So any list of “CJC-1295 and ipamorelin side effects” is built from two different drugs, tested in different people, by different routes.
CJC-1295 side effects in human studies
In the first study, 94% of people on CJC-1295 had at least one side effect, versus 29% on placebo. Effects other than hive-like rashes were more common at the higher doses of 125 and 250 mcg per kg.[1]
| Side effect | Study 1 (single dose) | Study 2 (repeat doses) |
|---|---|---|
| Injection-site reactions (redness, hardening, pain, itching) | About 70% | All treated subjects |
| Short-lived hive-like rash at the site | Almost 30% | Not reported separately |
| Headache | 63% vs 14% on placebo | 20% to 80% by group, 50% on placebo |
| Stomach and bowel effects | Diarrhea in 43%; loose stools in 100% at 250 mcg/kg | Nausea or abdominal pain in 20% |
| Flushing, warmth, low blood pressure | 30% | Flushing in 40% at low and 100% at high doses |
Source: FDA’s review of the published studies.[1]
Other findings:
- Flushing timing: it began within 30 minutes of the injection and resolved in 1 to 2 hours.[1]
- Dizziness: two people had dizziness and low blood pressure after their first dose, which did not recur.[1]
- Heart rate: in the pulsatility study of 12 healthy men,[10] heart rate rose with dose.[1]
- Lab tests: no consistent changes in blood or urine tests, glucose, liver tests or ECGs over the study period.[1]
- Hormone levels: IGF-1 rose above the normal range only at 250 mcg per kg.[1]
The study authors reported no serious adverse reactions.[3] FDA lists increased heart rate and the vasodilatory reaction among CJC-1295’s safety concerns.[6]
The 2006 trial death
In a phase 2 trial for HIV-related belly fat, a participant developed chest discomfort two hours after his 11th weekly dose and died of a heart attack about an hour later. His physician thought undiagnosed coronary artery disease was the most likely explanation. The trial was terminated and its data never published, so no link to the drug was established.[1][9]
Ipamorelin side effects in the surgery trial
Side effects were common in both groups, as expected after major surgery (87.5% on ipamorelin, 94.8% on placebo).[4] FDA’s review pulled out the differences:[2]
| Side effect | Ipamorelin | Placebo |
|---|---|---|
| Low potassium | 12.5% | 3.4% |
| Insomnia | 10.7% | 5.2% |
| High blood sugar at discharge | 14.3% | 8.6% |
| Serious adverse events | 17.9% | 15.5% |
Two patients on ipamorelin, both having colon cancer surgery, died after leaks at the bowel join. FDA said it is unclear whether the deaths were related to ipamorelin but counted them among its concerns.[2] FDA found no human safety data for injection under the skin.[6] More detail is in our ipamorelin side effects guide.
What raising growth hormone can do
Both peptides work by making the pituitary release more growth hormone, which raises IGF-1. FDA says their safety profile could resemble that of growth hormone drugs, whose labels warn of:[1]
- glucose intolerance and diabetes
- fluid retention
- raised pressure around the brain
- a possible increased risk of tumors
- pancreatitis, and in children, hip and spine problems
The 2026 review lists what clinicians see in people self-injecting these peptides: prolactin and cortisol rises, appetite changes, abnormal blood sugar, fluid retention, muscle and joint aches, and injection-site reactions.[5] It notes that prolactin and cortisol rises are mainly seen with older ghrelin-type peptides, and that ipamorelin tends to spare them.[5] That fits the original animal data: in pigs, ipamorelin did not raise ACTH or cortisol.[7]
Ipamorelin mimics ghrelin, the hunger hormone. In mice, it increased food intake and body fat through a pathway that did not depend on growth hormone.[8]
Animal and lab safety signals
FDA’s review of CJC-1295 with DAC also flagged:[1]
- Injection-site damage: bleeding, inflammation and tissue death at the site in rats and dogs given repeated daily injections.
- DNA damage: in one mouse study, 8 weeks of CJC-1295 enlarged the front of the pituitary gland and damaged pituitary cell DNA.
- No cancer studies: no 2-year studies exist for any form, and mice that overproduce GHRH develop pituitary overgrowth and tumors.
- Off-target binding: the DAC chemistry could attach to proteins other than albumin.
Product quality risks
FDA counted at least nine names for five CJC-1295-related substances and called the naming confusion a safety risk, because a patient may get a different substance than the one prescribed.[1] For both peptides, FDA warns of immune reactions from clumped peptide or impurities, and ipamorelin’s unnatural amino acids make it harder to test.[6] See our guides to peptide side effects and peptide injection-site reactions.
Who should be cautious
Talk carefully with a clinician before using either peptide if you:
- have diabetes, prediabetes or high blood sugar
- have had cancer, since growth hormone and IGF-1 are growth factors[1]
- have heart disease, low blood pressure or a fast heart rate
- have low potassium or take medicines that lower it
- are pregnant, trying to conceive or breastfeeding
- compete in tested sport: FDA noted in 2024 that the World Anti-Doping Agency prohibits CJC-1295 and other growth hormone secretagogues at all times[1]
For the doses behind these findings, see the CJC-1295 and ipamorelin dosage guide.
Questions to ask a clinician
- Is the CJC-1295 with or without DAC, and how do you know?
- Will you check my IGF-1, glucose and potassium before and during use?
- Which symptoms, such as chest pain, fainting or a racing heart, mean I should stop and seek care?
- Is there an FDA-approved option for my goal?
Report suspected side effects to your clinician and to FDA’s MedWatch program.
