Titus Thorne

Last Updated November 17, 2021

Titus Thorne

 November 17, 2021

There are two types of CJC-1295 peptide: CJC-1295 and CJC-1295 DAC.

You might be asking, “what’s the difference between two?”

It’s really just that CJC-1295 DAC has an added piece to the end of the peptide — called a “drug affinity complex” (hence the abbreviation “DAC”).

But that little piece changes how the modified peptide works. The biggest change is that it significantly prolongs the half-life up to 6 to 8 days. That means the peptide can continue to have an effect up to two weeks later. And because it works longer, there are some differences in dosing it, too.

If you want all the juicy details, you’re in the right place. Let’s dive in.

Buy CJC-1295 from the #1 online Peptides vendor in the world: Peptides Sciences

Disclaimer: ResearchPeptides.org contains information about products that are intended for laboratory and research use only, unless otherwise explicitly stated. This information, including any referenced scientific or clinical research, is made available for educational purposes only. ResearchPeptides.org makes every effort to ensure that any information it shares complies with national and international standards for clinical trial information and is committed to the timely disclosure of the design and results of all interventional clinical studies for innovative treatments publicly available or that may be made available. However, research is not considered conclusive. ResearchPeptides.org makes no claims that any products referenced can cure, treat or prevent any conditions, including any conditions referenced on its website or in print materials.

What Is CJC-1295?

CJC-1295 peptide, without DAC, has a number of synonyms. Around the web you’ll see it called “modified growth hormone-releasing factor (1-29)” or “Modified GRF (1-29)”, or even just ModGRF 1-29 for short. Some simply call it CJC-1295, without DAC.
All of these refer to a particular peptide compound that’s basically just a short chain of amino acids [1].

But this particular peptide has the same chemical structure as part of your body’s natural growth hormone-releasing hormone (GHRH) [2]. That means it has the same effect: It works to upregulate growth hormone levels in your blood [3].

Growth hormone (sometimes called human growth hormone, or HGH) matters because it’s involved in pretty much all of your important bodily functions. It helps your cells reproduce, grow and repair themselves [4]. So growth hormone (GH) can help with things like repairing tissue, building muscle, keeping skin healthy and more.

While your body naturally makes GH, it begins to make less and less of it as you age. That’s partly why you find that it takes longer for your body to recover as you get older. Because CJC-1295 stimulates your body to release more GH, it can have the effect of bringing your GH levels back in line with how they were when you were younger [5].

Ultimately, CJC-1295 HGH has the effect of making it easier and faster for the body to repair itself, build muscle and burn fat.

CJC-1295 dac

What Is CJC-1295 DAC?

CJC-1295 DAC is very similar to regular CJC-1295 — they’re both synthetic peptides that are a modified version of your body’s own GHRG (1-29).

The big difference between the two is that CJC-1295 DAC has an extra molecule added to the end of the peptide called drug affinity complex.

DAC is essentially a few nitrogen and oxygen atoms held together with some bonds. But those few atoms make a big difference in how the peptide is used in the body and how long it takes to break down.

The Differences?

So what’s the difference between CJC-1295 vs. CJC-1295 DAC?

Here are the basics.

Difference in Half-Life

One of the biggest differences is their half-life.

Regular CJC-1295 is closer to your body’s own peptide. That means it’s used by your body in much the same way. Your body’s own GHRH only has a half-life of a few minutes [6]. Like GHRH, CJC-1295 also has a very short half-life — about 30 minutes.

However, the extra DAC massively changes how your body uses the peptide. Basically, the DAC gives the peptide a lysine linker. That helps protect it when it is circulating around in the bloodstream and keeps it from being broken down.

The DAC also allows the peptide to better bind to the protein albumin in the blood, which, again, helps it continue to have an effect for a long time.

Together, this means that the extra little add-on drastically prolongs the half-life of CJC-1295 DAC in your blood plasma — it’s estimated to be about 6 to 8 days [3].

Difference in CJC-1295 Dosage

Because CJC-1295-DAC has a much longer half-life, it should be dosed differently than regular CJC-1295.

Here’s a brief difference in the dosing schedules of the two types of CJC-1295:

CJC-1295: Dr. William Seeds, in his book “Peptide Protocols” [7], recommends a CJC-1295 dosage of 1 mcg per kilogram of body weight. A saturation dosage is 100 mcg; that means that doses higher than that don’t add much to the release of GH, but may increase the risk of side effects. CJC-1295 can be used every day during a cycle.

CJC-1295 DAC:
Given its longer clearance time, you don’t need to take CJC-1295 DAC as often. Dr. Seeds says that a dose of 100 mcg taken twice a week is typically used as a starting saturation dose [7]. For a short-term treatment protocol or other research, it may be appropriate to take 100 mcg in a single daily injection daily.

But generally, research subjects should only be given CJC-1295 DAC once or twice a week.

Differences in Application

In general, the effects of CJC-1295 with and without DAC are the same. However, Dr. Seeds notes that CJC-1295 DAC is sometimes used for burns or for significant soft-tissue applications after some surgeries because it helps the body repair these types of tissues.

This may be one additional use of CJC-1295 DAC beyond the uses that the two have in common (which are building muscle, burning fat, anti-aging effects and better sleep).

Differences in Diet Restrictions

The purpose of CJC-1295 is to stimulate your body to produce growth hormone. The timing of meals and what the research subject is eating can interfere with that.

With CJC-1295, the half-life is short, so timing matters. You want to ensure that subjects take it on an empty stomach — at least two hours after eating. That will make sure that it has the desired effect and produces an elevation in GH levels. And, ideally, the subject will wait as long as possible after injection to eat (minimum of 30 minutes).

Since the half-life for CJC-1295 DAC is so long, there’s no dietary restriction with this form. Still, it’s beneficial to ensure compliance with the same guidelines of taking it on an empty stomach and not eating for at least 30 minutes after.

The ideal post-injection meal will be high in protein and moderate in fat with relatively low carbohydrates. The reason is that carbohydrates can affect insulin levels, and insulin can stop the effect of GH burning fat.

Differences in Naming

Another difference to keep in mind is that different vendors may use different naming conventions when selling these products. So make sure you don’t get confused.
For example, Peptide Sciences sells these peptides using the following names:

  • They call CJC-1295 with DAC “CJC-1295 DAC”
  • They call CJC-1295 without DAC “Mod GRF (1-29)”

So just be aware that if you’re looking for regular CJC-1295 and cannot find it, it could be because the vendor is calling it something else.

The Similarities?

These two peptides are mostly similar. That’s important to keep in mind.

Most importantly, they both have the same primary effect of increasing GH levels in the blood. Any additional benefits come indirectly through that increase in GH.

Also, they both raise GH levels in such a way that they don’t just increase GH release immediately. Instead, they stimulate the pituitary to release its GH following a natural pulsatile release schedule based on the circadian rhythm.

That’s a good thing. It means rather than a test subjects’ system being blasted with GH, GH goes up when it naturally would in their circadian rhythm. That’s better for the body.

CJC-1295 dac


CJC-1295 DAC Benefits

What do we know so far about CJC-1295 benefits?

Well, the main reported effect of CJC-1295 DAC is that it increases the amount of growth hormone in the plasma [3]. That, in turn, may entail beneficial effects for research subjects.

These include:

  • Increasing lean tissue and muscle mass. The bodybuilding community is excited about CJC-1295 because growth hormone makes it easier for the body to recover from a workout and put on muscle. Obviously, CJC-1295 bodybuilding doesn’t happen by itself: Research subjects will still need to work out to see changes to their body composition [8, 9].
  • Helping to burn fat. Growth hormone plays a large role in converting adipose tissue into energy. More growth hormone can help subjects burn through excess fat [8, 10].
  • Slowing down aging. This is one of the main uses. It works because growth hormone is involved in the process of creating collagen in the skin. So CJC-1295 and other growth hormone-releasing hormones can help your body repair and create thick, elastic and youthful skin [11, 12].
  • Helping to improve sleep. The precise role that growth hormone plays in sleep is not yet clear, but it’s fairly accepted that the substances that increase growth hormone also tend to have a beneficial effect on sleep [13].
  • Aiding with injury recovery. Growth hormone plays an essential role in repairing tissue; that’s why increasing it helps your body recover from injury. According to Dr. Seeds, CJC-1295 DAC may be especially effective in repairing tissue after severe burns or significant soft tissue damage [7].

CJC-1295 DAC Side Effects

It sounds like a miracle substance, right? So you might be wondering about the downsides.

As with any synthetic compound, some research subjects may experience side effects. Based on reports to date, these are typically rare and tend not to be severe. The majority of direct studies of CJC-1295 on human subjects have found few or no side effects in the short term. None of them have found severe side effects in the short term [3, 5, 7].

Still, it’s important to be aware of all the possibilities. Potential side effects of CJC-1295 include:

  • redness and tenderness at injection site
  • increased heart rate
  • headache
  • nausea
  • dizziness
  • flushing
  • hives
  • hyperactivity
  • difficulty swallowing
  • flu-like symptoms

Side effects are more likely to occur with larger doses. Starting with smaller doses can help research avoid severe side effects.

Unfortunately, we do not yet have sufficient clinical data to know much about the long-term safety of CJC-1295.

Where To Buy CJC-1295 DAC Online? | 2021 Guide

Our favorite place to buy CJC-1295, either with DAC or as ModGRF (1-29) (without DAC) is Peptide Sciences.

Peptide Sciences is easily the best source for peptides we’ve found. They’re legit and provide high-quality, research-grade products.

Here’s what we like about them:

  • Lab analyses to verify purity. You want to make sure you’re only using pure peptides for your research. Peptide Sciences provides lab analyses to show you the quality that you’re getting.
  • Convenient payment options. You can check out and pay with a number of payment options, including credit card, electronic payment options like Apple and Google pay, as well as several types of cryptocurrency.
  • Quick shipping. Peptide Sciences is based in the US, so delivery within the US happens within 2-3 business days. International shipping takes a bit longer but your product should still get to you within 7 to 10 business days.
  • High-quality customer service. If you ever have a problem with your order, you can actually get in touch with someone to fix it. The friendly team at Peptide Sciences responds to all emails and guarantees that if you’re not satisfied, they’ll make it right.

They even sell some peptide blends that you might find especially effective, such as a CJC-1295 Ipamorelin blend, as well as a Mod GRF (1-29) Ipamorelin blend. These convenient blends are just one more differentiator that makes Peptide Sciences the best.

Is CJC-1295 legal?

This is a super common question, and the answer is: yes. At least in the US and most other countries.

While CJC-1295 peptide is not a controlled substance, it is also not regulated for general consumption. That’s why it’s available for purchase for research only.

Buy CJC-1295 from our #1 recommended vendor...

CJC-1295 dac


CJC-1295 vs. CJC-1295 DAC | Verdict

The overall effect of CJC-1295 is essentially the same — with or without DAC. The original peptide and its modified version both elevate the amount of growth hormone in the blood.

That, in turn, has a number of well-documented effects on boosting the body’s ability to build, maintain and repair tissue. Results can include better muscle synthesis, faster fat burning, faster recovery from injury and younger-looking skin.

But there are some differences, the main one being that when CJC-1295 has DAC attached, it takes effect for much longer. That means it should typically be dosed with less frequency.

Not sure what would work best for your research? Try both versions and see what works best for your research subjects.


  1. Jetté, L., Léger, R., Thibaudeau, K., Benquet, C., Robitaille, M., Pellerin, I., … & Bridon, D. P. (2005). hGRF1-29-Albumin Bioconjugates Activate the GRF Receptor on the Anterior Pituitary in Rats: Identification of CJC-1295 as a Long Lasting GRF Analog. Endocrinology, 146(7), 3052–3058.
  2. Alba, M., Fintini, D., Sagazio, A., Lawrence, B., Castaigne, J. P., Frohman, L. A., & Salvatori, R. (2006). Once-daily administration of CJC-1295, a long-acting growth hormone-releasing hormone (GHRH) analog, normalizes growth in the GHRH knockout mouse. American Journal of Physiology-Endocrinology and Metabolism, 291(6), E1290-E1294.
  3. Teichman, S. L., Neale, A., Lawrence, B., Gagnon, C., Castaigne, J. P., & Frohman, L. A. (2006). Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults. The Journal of Clinical Endocrinology & Metabolism, 91(3), 799-805.
  4. Florini, J. R. (1987). Hormonal control of muscle growth. Muscle & Nerve: Official Journal of the American Association of Electrodiagnostic Medicine, 10(7), 577-598.
  5. Ionescu, M., & Frohman, L. A. (2006). Pulsatile secretion of growth hormone (GH) persists during continuous stimulation by CJC-1295, a long-acting GH-releasing hormone analog. The Journal of Clinical Endocrinology & Metabolism, 91(12), 4792-4797.
  6. Van Hout, M. C., & Hearne, E. (2016). Netnography of female use of the synthetic growth hormone CJC-1295: pulses and potions. Substance Use & Misuse, 51(1), 73-84.
  7. Seeds, W. (2020). Peptide protocols, volume 1. Seeds scientific performance research. https://affordablebookdeals.com/products/peptide-protocols-volume-one.
  8. Thompson, J. L., Butterfield, G. E., Gylfadottir, U. K., Yesavage, J., Marcus, R., Hintz, R. L., … & Hoffman, A. R. (1998). Effects of human growth hormone, insulin-like growth factor I, and diet and exercise on body composition of obese postmenopausal women. The Journal of Clinical Endocrinology & Metabolism, 83(5), 1477-1484.
  9. Welle, S., Thornton, C., Statt, M., & McHenry, B. (1996). Growth hormone increases muscle mass and strength but does not rejuvenate myofibrillar protein synthesis in healthy subjects over 60 years old. The Journal of Clinical Endocrinology & Metabolism, 81(9), 3239-3243.
  10. Taaffe, D. R., Pruitt, L., Reim, J., Hintz, R. L., Butterfield, G., Hoffman, A. R., & Marcus, R. (1994). Effect of recombinant human growth hormone on the muscle strength response to resistance exercise in elderly men. The Journal of Clinical Endocrinology & Metabolism, 79(5), 1361-1366.
  11. Ganceviciene, R., Liakou, A. I., Theodoridis, A., Makrantonaki, E., & Zouboulis, C. C. (2012). Skin anti-aging strategies. Dermato-endocrinology, 4(3), 308-319.
  12. Bartke, A. (2019). Growth hormone and aging: updated review. The World Journal of Men's Health, 37(1), 19-24.
  13. Ghigo, E., Arvat, E., Giordano, R., Broglio, F., Gianotti, L., Maccario, M., … & Camanni, F. (2001). Biologic activities of growth hormone secretagogues in humans. Endocrine, 14(1), 87-93.

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