Peptide Catalog

Retatrutide, also known as “GLP-3,” is an experimental weight-loss and diabetes drug being developed by Eli Lilly. It works by mimicking three different gut and pancreas hormones at once; the same hormone that drugs like Ozempic mimic, plus two others that Ozempic doesn’t touch.

Hitting all three signals together tells your body to feel full sooner, eat less, handle blood sugar better, and burn through stored fat more aggressively than single- or double-target drugs can. In clinical trials so far, people taking Retatrutide have lost substantially more weight than people on semaglutide (Ozempic/Wegovy) or tirzepatide (Mounjaro/Zepbound). Average losses in the range of twenty to twenty-four percent of body weight over about a year, which is closer to bariatric-surgery territory than typical drug results.

GLP-3 (RETA) is given as a once-weekly subcutaneous injection. As with similar drugs, side effects are mostly digestive and include nausea, vomiting, and diarrhea, especially as the dose is increased. It’s still in trials and not yet on the market through normal pharmacy channels, so any version available now comes from peptide-therapy and research-chemical suppliers rather than approved sources.

Retatrutide, also known as “GLP-3,” is an experimental weight-loss and diabetes drug being developed by Eli Lilly. It works by mimicking three different gut and pancreas hormones at once; the same hormone that drugs like Ozempic mimic, plus two others that Ozempic doesn’t touch.

Hitting all three signals together tells your body to feel full sooner, eat less, handle blood sugar better, and burn through stored fat more aggressively than single- or double-target drugs can.

In clinical trials so far, people taking retatrutide have lost substantially more weight than people on semaglutide (Ozempic/Wegovy) or tirzepatide (Mounjaro/Zepbound). Average losses in the range of twenty to twenty-four percent of body weight over about a year, which is closer to bariatric-surgery territory than typical drug results.

GLP-3 (RETA) is given as a once-weekly subcutaneous injection. As with similar drugs, side effects are mostly digestive and include nausea, vomiting, and diarrhea, especially as the dose is increased.

It’s still in trials and not yet on the market through normal pharmacy channels, so any version available now comes from peptide-therapy and research-chemical suppliers rather than approved sources.

Retatrutide, also known as “GLP-3,” is an experimental weight-loss and diabetes drug being developed by Eli Lilly. It works by mimicking three different gut and pancreas hormones at once; the same hormone that drugs like Ozempic mimic, plus two others that Ozempic doesn’t touch.

Hitting all three signals together tells your body to feel full sooner, eat less, handle blood sugar better, and burn through stored fat more aggressively than single- or double-target drugs can.

In clinical trials so far, people taking retatrutide have lost substantially more weight than people on semaglutide (Ozempic/Wegovy) or tirzepatide (Mounjaro/Zepbound). Average losses in the range of twenty to twenty-four percent of body weight over about a year, which is closer to bariatric-surgery territory than typical drug results.

GLP-3 (RETA) is given as a once-weekly subcutaneous injection. As with similar drugs, side effects are mostly digestive and include nausea, vomiting, and diarrhea, especially as the dose is increased.

It’s still in trials and not yet on the market through normal pharmacy channels, so any version available now comes from peptide-therapy and research-chemical suppliers rather than approved sources.

MOTS-c is an unusual peptide because, unlike almost every other protein in your body, it’s coded for by your mitochondrial DNA rather than the DNA in the cell nucleus. Mitochondria are the tiny power plants inside your cells that turn food into usable energy, and MOTS-C is a signal they send out to coordinate how the rest of the body handles fuel, especially how muscles take up and burn sugar and fat.

Levels naturally drop with age, and researchers think this decline is part of why metabolism slows down and insulin sensitivity worsens as people get older.

In animal studies, giving MOTS-C improves insulin sensitivity, helps muscles burn fat more efficiently, protects against diet-induced weight gain, and appears to mimic some of the metabolic benefits of exercise even in animals that aren’t moving much.

People in peptide therapy circles use it for better blood sugar control, easier fat loss, more energy and endurance, faster recovery from workouts, and general anti-aging effects on metabolism.

MOCS-C is typically given as a subcutaneous injection a few times a week. As with most peptides, all the supporting research is in mice and lab studies, with only a small handful of early human trials so far, so the strong claims circulating online are running well ahead of what’s actually been demonstrated in people.

BPC-157 is a lab-made peptide based on a small fragment of a protein found naturally in the human stomach. The letters stand for “body protective compound,” and it was first studied in the 1990s by Croatian researchers who were looking into why the stomach lining heals so quickly despite being exposed to acid all day.

In animal studies, it appears to accelerate healing across a wide range of tissues, including muscles, tendons, ligaments, the gut lining, skin wounds, and even nerve and bone tissue. It achieves this partly by encouraging the growth of new small blood vessels into injured areas, which brings in the oxygen and nutrients tissues need to repair themselves.

People in peptide therapy circles use it for faster recovery from injuries (especially stubborn tendon and ligament problems that don’t respond well to rest), reduced inflammation, gut healing for issues like leaky gut or inflammatory bowel conditions, and general protection against the kind of wear and tear that comes with hard training.

BPC-157 is usually injected under the skin near the injury site, though some users take it as a capsule for gut-related issues, as it appears to survive stomach acid reasonably well. Effects on injuries typically show up within a few weeks of daily use. There are very few human studies, so the strong reputation it has online is largely based on animal data and personal accounts.

GHK-Cu is a small naturally occurring peptide with just three amino acids. It is bound to a single copper atom, which is where the “Cu” in the name comes from (Cu is the chemical symbol for copper).

Your body makes it on its own, and levels in your blood are highest when you’re young and drop steadily as you age, falling by roughly two-thirds between your twenties and your sixties. Researchers think this decline is part of the reason older skin and tissue heal more slowly and appear less youthful.

GHK-Cu appears to do a remarkable range of things: it signals skin cells to produce more collagen and elastin, encourages new blood vessel growth into healing tissue, tamps down inflammation, acts as an antioxidant, and even seems to nudge gene activity in patterns associated with younger, healthier tissue. People use it for smoother, firmer skin, faster wound healing, reduced fine lines and sun damage, thicker hair growth, and general anti-aging effects on skin and connective tissue.

Unlike most other peptides in this family, GHK-Cu is most often used as a topical cream or serum applied directly to the skin or scalp, though it’s also available as an injection under the skin for people targeting deeper or more system-wide effects. The topical version has been used in cosmetic skincare products for decades, and the human research base, at least for skin applications, is significantly larger than for most other peptides.

GLOW is a blend of three peptides (BPC-157, TB-500, and GHK-Cu) combined into a single injection aimed specifically at skin, hair, and overall appearance.

The idea is that each of the three peptides targets a different part of what makes skin and hair look healthy, so combining them produces results that none of them delivers on their own. BPC-157 contributes to general tissue repair and reduces inflammation; TB-500 adds broader healing effects and encourages new blood vessel growth that brings nutrients to skin and hair follicles; and GHK-Cu drives collagen production, skin renewal, and copper-related anti-aging effects that have made it a mainstay of high-end skincare for decades.

People use GLOW for smoother, firmer skin; fewer fine lines; faster healing of blemishes and scars; improved skin tone and texture; thicker, healthier hair growth; stronger nails; and a general youthful-looking quality to the skin that topical products struggle to match.

GLOW is typically taken as an injection under the skin a few times a week during a treatment cycle of a couple of months, then tapered to a maintenance schedule. Effects usually build gradually over six to twelve weeks of consistent use.

The same caveat applies to GLOW as to its individual ingredients: the human research base behind the specific blend is essentially nonexistent, and what’s known comes from research on each peptide separately, mostly in animal studies, plus personal accounts from users.

KLOW is a blend of four peptides (KPV, GHK-Cu, TB-500, and BPC-157) combined into a single injection aimed at skin, hair, healing, and general appearance. It’s essentially the GLOW blend with KPV added, and the idea is that each peptide targets a different aspect of what keeps skin and connective tissue healthy, so stacking them together covers more ground than any one of them alone.

KPV contributes anti-inflammatory and antimicrobial effects that calm irritated skin and help clear breakouts; GHK-Cu drives collagen production and the copper-related skin renewal used in high-end skincare; TB-500 adds broader healing and encourages new blood vessel growth that feeds skin and hair follicles; and BPC-157 contributes general tissue repair and reduced inflammation.

People use KLOW for smoother, firmer skin; fewer fine lines and blemishes; faster healing of scars and acne; improved skin tone and texture; thicker, healthier hair; stronger nails; calming of inflammatory skin conditions like eczema and rosacea; and an overall youthful-looking quality to skin and connective tissue.

KLOW is typically taken as an injection under the skin a few times a week during a treatment cycle of a couple of months, then tapered to maintenance dosing. Effects usually build gradually over six to twelve weeks of consistent use.

The same caveat applies to KLOW and its individual ingredients as most peptides: there’s essentially no human research on the specific blend, and what’s known comes from research on each peptide separately, mostly in animal studies, plus personal accounts from users.

Selank is a lab-made peptide developed in Russia in the 1990s, based on a small fragment of a natural immune-system molecule called tuftsin, with a few amino acids added to make it more stable in the body.

Like its cousin Semax, it’s an approved medicine in Russia and a few neighboring countries, where it’s prescribed mainly for anxiety disorders and as a milder alternative to traditional anti-anxiety drugs like benzodiazepines. It appears to work by nudging the brain’s GABA system, the same calming pathway that drugs like Valium and Xanax target, but through a gentler, more indirect route that doesn’t cause sedation, dependence, or the foggy-headed feeling those drugs are known for.

Selank also appears to influence levels of BDNF and several brain chemicals involved in mood and stress, and it has mild effects on the immune system, which may explain why some users report fewer colds during use.

People take Selank for reduced anxiety without sedation, calmer response to stress, better mood, sharper focus and memory, improved sleep quality, and a general sense of even-keeled steadiness during demanding periods.

Like Semax, it’s most often taken as nasal drops or a nasal spray rather than an injection, with effects typically felt within an hour and lasting most of the day. Users often use Semax once or twice a day during stressful stretches rather than continuously.

The human research base is larger than for most peptides, though nearly all of it comes from Russian clinical work that isn’t widely translated, which is part of why Selank stays relatively unknown in Western medicine despite a decades-long track record of approved use.

Semax is a lab-made peptide developed in Russia in the 1980s, based on a small fragment of the natural hormone ACTH (adrenocorticotropic hormone), with a few amino acids added to make it more stable.

Unlike most peptides, it’s actually an approved medicine in Russia and a few neighboring countries, where it’s prescribed for stroke recovery, cognitive problems, optic nerve disorders, and ADHD-like attention issues in children. It mainly works in the brain, where it appears to boost levels of the protein BDNF (brain-derived neurotrophic factor), sometimes described as fertilizer for brain cells. It supports the growth, repair, and connectivity of neurons. It also seems to nudge the brain’s dopamine and serotonin systems, improving focus, mood, and stress resilience.

People use Semax for sharper mental focus and concentration, better memory, faster learning, improved mood, reduced anxiety, protection of brain tissue after injuries or strokes, and general cognitive enhancement of the kind that gets called “nootropic.”

Unusually for a peptide, it’s most often taken as nasal drops or a nasal spray rather than an injection, since the nasal route lets it reach the brain quickly and effectively without needles. Effects are typically felt within an hour or two and last several hours, with users often dosing once or twice a day when they want a cognitive lift.

The human research base is meaningfully larger than for most peptides, but nearly all of it was conducted in Russia, and much of it isn’t readily available in English, which is part of why Semax remains relatively obscure in Western medicine despite decades of clinical use.

Retatrutide, also known as “GLP-3,” is an experimental weight-loss and diabetes drug being developed by Eli Lilly. It works by mimicking three different gut and pancreas hormones at once; the same hormone that drugs like Ozempic mimic, plus two others that Ozempic doesn’t touch.

Hitting all three signals together tells your body to feel full sooner, eat less, handle blood sugar better, and burn through stored fat more aggressively than single- or double-target drugs can. In clinical trials so far, people taking Retatrutide have lost substantially more weight than people on semaglutide (Ozempic/Wegovy) or tirzepatide (Mounjaro/Zepbound). Average losses in the range of twenty to twenty-four percent of body weight over about a year, which is closer to bariatric-surgery territory than typical drug results.

GLP-3 (RETA) is given as a once-weekly subcutaneous injection. As with similar drugs, side effects are mostly digestive and include nausea, vomiting, and diarrhea, especially as the dose is increased. It’s still in trials and not yet on the market through normal pharmacy channels, so any version available now comes from peptide-therapy and research-chemical suppliers rather than approved sources.

Retatrutide, also known as “GLP-3,” is an experimental weight-loss and diabetes drug being developed by Eli Lilly. It works by mimicking three different gut and pancreas hormones at once; the same hormone that drugs like Ozempic mimic, plus two others that Ozempic doesn’t touch.

Hitting all three signals together tells your body to feel full sooner, eat less, handle blood sugar better, and burn through stored fat more aggressively than single- or double-target drugs can.

In clinical trials so far, people taking retatrutide have lost substantially more weight than people on semaglutide (Ozempic/Wegovy) or tirzepatide (Mounjaro/Zepbound). Average losses in the range of twenty to twenty-four percent of body weight over about a year, which is closer to bariatric-surgery territory than typical drug results.

GLP-3 (RETA) is given as a once-weekly subcutaneous injection. As with similar drugs, side effects are mostly digestive and include nausea, vomiting, and diarrhea, especially as the dose is increased.

It’s still in trials and not yet on the market through normal pharmacy channels, so any version available now comes from peptide-therapy and research-chemical suppliers rather than approved sources.

Retatrutide, also known as “GLP-3,” is an experimental weight-loss and diabetes drug being developed by Eli Lilly. It works by mimicking three different gut and pancreas hormones at once; the same hormone that drugs like Ozempic mimic, plus two others that Ozempic doesn’t touch.

Hitting all three signals together tells your body to feel full sooner, eat less, handle blood sugar better, and burn through stored fat more aggressively than single- or double-target drugs can.

In clinical trials so far, people taking retatrutide have lost substantially more weight than people on semaglutide (Ozempic/Wegovy) or tirzepatide (Mounjaro/Zepbound). Average losses in the range of twenty to twenty-four percent of body weight over about a year, which is closer to bariatric-surgery territory than typical drug results.

GLP-3 (RETA) is given as a once-weekly subcutaneous injection. As with similar drugs, side effects are mostly digestive and include nausea, vomiting, and diarrhea, especially as the dose is increased.

It’s still in trials and not yet on the market through normal pharmacy channels, so any version available now comes from peptide-therapy and research-chemical suppliers rather than approved sources.

CJC-1295 is a lab-made peptide that works much like tesamorelin. It mimics your brain’s natural “release some growth hormone” signal and tells your pituitary gland to put out a pulse of your body’s own growth hormone.

The main difference is staying power. Plain CJC-1295 only lasts about 30 minutes, but a modified version called CJC-1295 with DAC (short for “drug affinity complex”) binds to a protein in your blood and keeps working for roughly a week from a single dose. The non-DAC version, sometimes called modified GRF 1-29 or just “CJC-1295 without DAC,” produces shorter, more natural-looking growth hormone pulses and is the version most commonly paired with ipamorelin.

People in peptide therapy circles use CJC-1295 for benefits such as fat loss, increased lean muscle, better sleep quality, faster recovery from exercise, improved skin and joint health, and general anti-aging effects.

CJC-1295 is typically given as a subcutaneous injection, with the short-acting version dosed once or twice a day (often at night) and the long-acting DAC version dosed once or twice a week. As with other peptides, the effects build over weeks to months and gradually fade after stopping.

Ipamorelin is a small lab-made protein, just five amino acids long, that tells your pituitary gland to release a pulse of your body’s own growth hormone. It does this by mimicking ghrelin, a natural hormone you already produce, and latching onto the same receptor ghrelin uses.

Ipamorelin was originally developed by a Danish drug company in the 1990s and tested for medical uses before being set aside.

People in the peptide therapy world use it for benefits like more lean muscle, less body fat, better sleep, quicker recovery from workouts, and general anti-aging effects. Compared to other peptides that do similar things, ipamorelin is considered “cleaner” because it doesn’t spike stress hormones or cause the intense hunger that some of its cousins do. Ipamorelin is usually paired with a similar peptide called CJC-1295.

Tesamorelin and ipamorelin are often used together because they nudge your body to release its own growth hormone through two different pathways simultaneously, producing a bigger, more natural-feeling pulse than either alone.

Tesamorelin mimics the brain’s natural “release some growth hormone” signal, while ipamorelin mimics ghrelin and presses a separate button on the pituitary gland that also triggers release. Hitting both buttons at once tends to amplify the effect, as pressing the gas pedal while shifting into a higher gear amplifies a car’s acceleration.

People in peptide therapy circles use this combination for benefits like fat loss (especially the stubborn deep belly fat that tesamorelin targets well), more lean muscle, better sleep quality, faster recovery from exercise, improved skin and connective tissue, and general anti-aging effects.

Tesa/Ipa is usually given as a once-daily injection under the skin, often at night before bed, since that’s when your body naturally releases the largest growth hormone pulse. The effects tend to build over weeks to months and gradually fade after stopping.

Tesamorelin is a lab-made version of a natural hormone your brain produces called growth hormone-releasing hormone. When injected, it travels to your pituitary gland and tells it to release more of your body’s own growth hormone, much like the natural signal would.

Tesamorelin was developed specifically to treat a condition where people with HIV who’ve been on long-term antiretroviral medication build up excess fat around their internal organs in the belly area; a stubborn kind of fat that’s hard to lose through diet and exercise alone. In studies, tesamorelin reliably shrinks that deep belly fat over a few months of daily use.

Outside of that specific medical use, it’s also popular in “peptide therapy” circles, often stacked with ipamorelin, where people use it for fat loss, more lean muscle, better sleep, and general anti-aging effects. It’s typically given as a once-daily injection under the skin, and the fat-loss effects tend to fade once you stop using it.

KPV is a tiny lab-made peptide that is just three amino acids long. It is named for the single-letter codes of those amino acids (lysine, proline, valine) that come from the tail end of the same natural hormone that Melanotan I and II are based on, alpha-MSH.

While the rest of the alpha-MSH molecule handles pigmentation and other effects, this short tail fragment turns out to carry most of the hormone’s anti-inflammatory power on its own, without any skin-darkening or broader effects. It works by entering cells and tamping down the chemical signals that drive inflammation, particularly in the gut lining and skin.

In animal and lab studies, it’s shown impressive effects against inflammatory bowel conditions like Crohn’s disease and ulcerative colitis, inflammatory skin conditions, and various infections. It also appears to have direct antimicrobial activity against bacteria, fungi, and some viruses, which is unusual for an anti-inflammatory compound.

People in peptide therapy circles use it for relief from inflammatory bowel issues, leaky gut, inflammatory skin conditions like eczema and psoriasis, joint inflammation, slow-healing wounds, and chronic low-grade inflammation generally.

KPV is typically taken by mouth as a capsule for gut-related issues, as an injection under the skin for systemic effects, or as a topical cream for skin conditions. It’s often paired with BPC-157 for gut healing, since the two work through different pathways and seem to complement each other well.

The human research base is thin. Most of what’s known comes from animal studies and lab work, but the safety profile in those studies has been notably clean, partly because the peptide is so small and breaks down quickly in the body.

Thymosin alpha-1 is a lab-made version of a natural peptide your thymus gland produces. The thymus is a small organ behind your breastbone that’s central to training and coordinating your immune system, especially when you’re young. Thymus activity drops sharply with age, and along with it, the body’s supply of thymosin alpha-1 and the immune support it provides.

The synthetic version was developed to restore that signal and help the immune system respond more effectively to threats. It mainly works by tuning up immune cells that hunt down viruses, bacteria, and abnormal cells, particularly T cells and natural killer cells, while also calming overactive immune responses, an unusual combination that lets it both boost immunity and reduce inappropriate inflammation at the same time.

Thymosin A1 is approved in over 30 countries (though not the United States) under brand names such as Zadaxin, where it’s prescribed for chronic hepatitis B and C, as an immune booster for cancer patients during chemotherapy, and to improve vaccine response in people with weak immune systems.

People in peptide therapy circles use it for stronger resistance to infections, faster recovery from illness, support during cancer treatment, relief from chronic inflammatory conditions and autoimmune issues, better response to vaccinations, and general immune support as they age.

Thymosin A1 is typically given by injection under the skin, usually twice a week for several months. Thymosin alpha-1 has one of the strongest human research bases, with decades of clinical use and numerous well-designed trials supporting its approved indications, though most of that research focuses on serious medical conditions rather than the general wellness uses it’s marketed for in peptide therapy circles.

PT-141, also called bremelanotide, is a lab-made peptide belonging to the same family as Melanotan II. It was actually developed from Melanotan II after researchers noticed that one of the side effects users kept reporting was strong sexual arousal.

Drug developers stripped away the parts of the molecule responsible for skin pigmentation and other effects, keeping only the part that activates the brain pathways involved in sexual desire. Unlike drugs in the Viagra family, which work on blood flow to the genitals, PT-141 works in the brain itself, specifically on receptors in the regions that govern sexual motivation and arousal. PT-141 can produce desire and response even in situations where blood flow drugs don’t help, including in women.

PT-141 is actually an approved medicine in the United States under the brand name Vyleesi, prescribed for low sexual desire in premenopausal women, and was studied extensively for erectile dysfunction in men.

People use PT-141 for increased sexual desire and arousal, stronger and more reliable erections, improved sexual function in situations where Viagra-type drugs haven’t worked well, and a renewed interest in sex in cases where it’s faded due to age, stress, medication side effects, or relationship-length familiarity.

You usually administer PT-141 as an injection under the skin or a nasal spray, taken about thirty to forty-five minutes before sexual activity rather than on a daily schedule. Effects usually last several hours.

Side effects can include nausea (sometimes significant, especially with the first few doses), facial flushing, headache, and temporary increases in blood pressure, which is why the approved version comes with cautions for people with heart conditions.

Of the peptides on this list, PT-141 has one of the more solid human research bases, with proper clinical trials behind both the approved women’s indication and the abandoned men’s program.

MOTS-c is an unusual peptide because, unlike almost every other protein in your body, it’s coded for by your mitochondrial DNA rather than the DNA in the cell nucleus. Mitochondria are the tiny power plants inside your cells that turn food into usable energy, and MOTS-C is a signal they send out to coordinate how the rest of the body handles fuel, especially how muscles take up and burn sugar and fat.

Levels naturally drop with age, and researchers think this decline is part of why metabolism slows down and insulin sensitivity worsens as people get older.

In animal studies, giving MOTS-C improves insulin sensitivity, helps muscles burn fat more efficiently, protects against diet-induced weight gain, and appears to mimic some of the metabolic benefits of exercise even in animals that aren’t moving much.

People in peptide therapy circles use it for better blood sugar control, easier fat loss, more energy and endurance, faster recovery from workouts, and general anti-aging effects on metabolism.

MOCS-C is typically given as a subcutaneous injection a few times a week. As with most peptides, all the supporting research is in mice and lab studies, with only a small handful of early human trials so far, so the strong claims circulating online are running well ahead of what’s actually been demonstrated in people.

NAD+ isn’t actually a peptide. It stands for nicotinamide adenine dinucleotide, and it’s a small molecule (technically a coenzyme) that every cell in your body uses constantly to turn food into energy and to run hundreds of other essential chemical reactions. Think of it as a kind of rechargeable battery that your cells pass around to power their work.

Levels drop significantly with age. By middle age, you have roughly half the NAD+ you had as a young adult. Researchers have linked this decline to many of the hallmarks of aging, including slower metabolism, reduced DNA repair, mitochondrial decline, and chronic inflammation. NAD+ is also required for a family of proteins called sirtuins to do their job, which is often described as turning on the body’s longevity and stress-resistance pathways. People use NAD+ for more energy, sharper mental focus, better sleep, faster recovery from exercise, reduced symptoms of aging, and, in some cases, support for addiction recovery, since it appears to ease withdrawal and cravings.

It’s most commonly delivered as an intravenous drip at a clinic, since the molecule is too large and fragile to absorb well from a pill, though injections under the skin and nasal sprays are also available. IV sessions typically last anywhere from one to several hours and are often done in a series spread over a couple of weeks, with maintenance doses afterward. Many users report a flushing sensation or chest pressure during the drip when the rate is too fast, which fades when the rate is slowed. The human research base is growing, but still thin. There’s solid evidence that NAD+ levels matter for health, but much less evidence yet on how much benefit comes from supplementing it directly versus other approaches like its precursors, NR (nicotinamide riboside) and NMN (nicotinamide mononucleotide).

SS-31, also called elamipretide, is a lab-made peptide designed to slip inside your cells and target the mitochondria, which are the tiny power plants that turn food into usable energy. Once inside, it binds to a specific lipid called cardiolipin, which lines the inner mitochondrial membrane and is essential for efficient energy production.

As mitochondria age or become damaged, cardiolipin breaks down, energy production declines, and mitochondria begin leaking harmful free radicals that damage the rest of the cell. SS-31 appears to stabilize cardiolipin and restore mitochondria to a state closer to their healthy, younger state, improving energy output and reducing free-radical damage.

SS-31 was developed as a proper pharmaceutical candidate and has been through clinical trials for several serious conditions, including a rare genetic mitochondrial disease called Barth syndrome, age-related macular degeneration, heart failure, and the muscle weakness that comes with aging. Results have been mixed but encouraging enough that development is still ongoing.

People in peptide therapy circles use it for more energy and stamina, faster recovery from exercise, better cognitive function, improved heart and eye health, and general anti-aging effects driven by healthier mitochondria. It’s typically given as a daily injection under the skin.

SS-31 has one of the more substantial human research bases, since it’s been studied in real clinical trials for over a decade, though it still hasn’t crossed the finish line to formal approval for any condition.

ARA-290, also called cibinetide, is a lab-made peptide built from a small piece of erythropoietin, the natural hormone your kidneys produce to tell your bone marrow to make more red blood cells.

Researchers discovered that erythropoietin performs two distinct functions in the body: the well-known one of boosting red blood cell production, and a lesser-known one of protecting and repairing nerves and other tissues from damage.

ARA-290 was specifically designed to target only the second job, the tissue-repair signal, without affecting the red blood cell side, sidestepping the heart and stroke risks that come with raising red blood cell counts too high. It works by calming overactive immune responses and protecting nerves from the kind of damage that causes chronic pain.

In clinical trials, it has been studied mostly for sarcoidosis-related nerve pain and for diabetic nerve damage, with promising results for reducing pain and improving small-fiber nerve function.

People in peptide therapy circles use it for relief from chronic nerve pain, neuropathy from diabetes or chemotherapy, inflammatory conditions, and slow-healing tissue damage that hasn’t responded to other treatments.

ARA-290 is typically given as a daily injection under the skin during treatment cycles of a few weeks to a few months. Compared to most peptides on this list, ARA-290 has a significantly stronger human research base, since it was developed as a bona fide pharmaceutical candidate and has undergone several proper clinical trials, though it still hasn’t crossed the finish line to formal approval anywhere.

BPC-157 is a lab-made peptide based on a small fragment of a protein found naturally in the human stomach. The letters stand for “body protective compound,” and it was first studied in the 1990s by Croatian researchers who were looking into why the stomach lining heals so quickly despite being exposed to acid all day.

In animal studies, it appears to accelerate healing across a wide range of tissues, including muscles, tendons, ligaments, the gut lining, skin wounds, and even nerve and bone tissue. It achieves this partly by encouraging the growth of new small blood vessels into injured areas, which brings in the oxygen and nutrients tissues need to repair themselves.

People in peptide therapy circles use it for faster recovery from injuries (especially stubborn tendon and ligament problems that don’t respond well to rest), reduced inflammation, gut healing for issues like leaky gut or inflammatory bowel conditions, and general protection against the kind of wear and tear that comes with hard training.

BPC-157 is usually injected under the skin near the injury site, though some users take it as a capsule for gut-related issues, as it appears to survive stomach acid reasonably well. Effects on injuries typically show up within a few weeks of daily use. There are very few human studies, so the strong reputation it has online is largely based on animal data and personal accounts.

BPC-157 and TB-500 are often used together because they appear to promote tissue healing through different but complementary pathways, and people who use them report that the combination works better than either alone.

BPC-157 is generally credited with localized repair, speeding up healing right around where it’s injected, which is why people often inject it near the specific muscle, tendon, or joint that’s bothering them. TB-500 spreads more widely throughout the body and is credited with broader, systemic effects that can reach injuries away from the injection site, as well as making connective tissue more flexible and resilient overall.

People in peptide therapy circles use this combination for faster recovery from injuries (especially stubborn tendon, ligament, and joint problems), reduced chronic inflammation, healing of gut issues, better range of motion, and general protection against training wear and tear. It’s typically taken as injections under the skin, with BPC-157 dosed once or twice a day near the problem area and TB-500 dosed once or twice a week anywhere convenient. Effects usually build over a few weeks of consistent use.

The same caveat applies as with each peptide alone: nearly all the supporting research is in animals, with very little human clinical data behind the combination.

GHK-Cu is a small naturally occurring peptide with just three amino acids. It is bound to a single copper atom, which is where the “Cu” in the name comes from (Cu is the chemical symbol for copper).

Your body makes it on its own, and levels in your blood are highest when you’re young and drop steadily as you age, falling by roughly two-thirds between your twenties and your sixties. Researchers think this decline is part of the reason older skin and tissue heal more slowly and appear less youthful.

GHK-Cu appears to do a remarkable range of things: it signals skin cells to produce more collagen and elastin, encourages new blood vessel growth into healing tissue, tamps down inflammation, acts as an antioxidant, and even seems to nudge gene activity in patterns associated with younger, healthier tissue. People use it for smoother, firmer skin, faster wound healing, reduced fine lines and sun damage, thicker hair growth, and general anti-aging effects on skin and connective tissue.

Unlike most other peptides in this family, GHK-Cu is most often used as a topical cream or serum applied directly to the skin or scalp, though it’s also available as an injection under the skin for people targeting deeper or more system-wide effects. The topical version has been used in cosmetic skincare products for decades, and the human research base, at least for skin applications, is significantly larger than for most other peptides.

GLOW is a blend of three peptides (BPC-157, TB-500, and GHK-Cu) combined into a single injection aimed specifically at skin, hair, and overall appearance.

The idea is that each of the three peptides targets a different part of what makes skin and hair look healthy, so combining them produces results that none of them delivers on their own. BPC-157 contributes to general tissue repair and reduces inflammation; TB-500 adds broader healing effects and encourages new blood vessel growth that brings nutrients to skin and hair follicles; and GHK-Cu drives collagen production, skin renewal, and copper-related anti-aging effects that have made it a mainstay of high-end skincare for decades.

People use GLOW for smoother, firmer skin; fewer fine lines; faster healing of blemishes and scars; improved skin tone and texture; thicker, healthier hair growth; stronger nails; and a general youthful-looking quality to the skin that topical products struggle to match.

GLOW is typically taken as an injection under the skin a few times a week during a treatment cycle of a couple of months, then tapered to a maintenance schedule. Effects usually build gradually over six to twelve weeks of consistent use.

The same caveat applies to GLOW as to its individual ingredients: the human research base behind the specific blend is essentially nonexistent, and what’s known comes from research on each peptide separately, mostly in animal studies, plus personal accounts from users.

KLOW is a blend of four peptides (KPV, GHK-Cu, TB-500, and BPC-157) combined into a single injection aimed at skin, hair, healing, and general appearance. It’s essentially the GLOW blend with KPV added, and the idea is that each peptide targets a different aspect of what keeps skin and connective tissue healthy, so stacking them together covers more ground than any one of them alone.

KPV contributes anti-inflammatory and antimicrobial effects that calm irritated skin and help clear breakouts; GHK-Cu drives collagen production and the copper-related skin renewal used in high-end skincare; TB-500 adds broader healing and encourages new blood vessel growth that feeds skin and hair follicles; and BPC-157 contributes general tissue repair and reduced inflammation.

People use KLOW for smoother, firmer skin; fewer fine lines and blemishes; faster healing of scars and acne; improved skin tone and texture; thicker, healthier hair; stronger nails; calming of inflammatory skin conditions like eczema and rosacea; and an overall youthful-looking quality to skin and connective tissue.

KLOW is typically taken as an injection under the skin a few times a week during a treatment cycle of a couple of months, then tapered to maintenance dosing. Effects usually build gradually over six to twelve weeks of consistent use.

The same caveat applies to KLOW and its individual ingredients as most peptides: there’s essentially no human research on the specific blend, and what’s known comes from research on each peptide separately, mostly in animal studies, plus personal accounts from users.

TB-500 is a lab-made version of a fragment of a natural protein called thymosin beta-4, which your body produces in nearly every cell, especially in blood platelets and wound fluid. Its main job in the body is to help cells move where they need to go during healing. Think of it as a kind of traffic signal that tells repair cells to migrate into damaged areas and get to work.

In animal studies, it appears to accelerate healing of muscles, tendons, ligaments, skin, heart tissue, and even the cornea, partly by promoting new blood vessel growth and partly by reducing inflammation and scar tissue formation.

People in peptide therapy circles often pair it with BPC-157 because the two seem to work through different but complementary pathways. BPC-157 is often credited with localized tissue repair, while TB-500 is credited with broader, systemic healing effects that extend beyond the injection site. Users take it in the hope of faster recovery from injuries, more flexible and resilient connective tissue, reduced chronic inflammation, and improved range of motion in stiff or previously injured joints. It’s usually given as an injection under the skin once or twice a week, since it spreads throughout the body rather than staying in place.

As with BPC-157, most of what’s known comes from animal studies, lab-dish experiments, and personal accounts rather than proper clinical trials.

DSIP stands for delta sleep-inducing peptide, named for the deep, slow brain waves, called delta waves, that dominate during the deepest stage of sleep. It was discovered in the 1970s by Swiss researchers who isolated it from the blood of rabbits in deep sleep, on the theory that something in their bloodstream might be carrying a “sleep signal” that could be identified and reproduced.

The peptide they found is naturally produced in the brain and appears to play a role in regulating sleep cycles, though decades later, researchers still don’t fully understand exactly how it works or what all its jobs in the body are. In animal and early human studies, it has shown an unusual range of effects: it appears to improve sleep quality, especially deep, restorative sleep, while also helping to normalize disrupted sleep patterns rather than simply knocking people out, as a sleeping pill does. It also seems to blunt the body’s stress response, ease certain kinds of chronic pain, and may help stabilize mood.

People use DSIP for better, more restorative sleep, an easier time falling asleep during stressful periods, reduced effects of jet lag or shift work, lower stress and anxiety, relief from chronic pain conditions, and help breaking out of disordered sleep patterns. It’s typically taken as an injection under the skin, usually in the evening before bed, though some users take it earlier when targeting stress rather than sleep specifically. The human research base is thin and mostly decades old, with most modern interest coming from peptide therapy circles rather than active clinical research, so the strong claims about it online are running well ahead of what’s been firmly established.

Epitalon is a lab-made peptide developed in Russia in the 1980s by a researcher named Vladimir Khavinson, based on a natural substance produced by the pineal gland, a small gland deep in the brain that regulates sleep, hormones, and biological aging. It’s a short chain of just four amino acids, designed to mimic a longer pineal extract called epithalamin that earlier Russian research had linked to slower aging and longer lifespan in animals.

Epitalon’s main claim to fame is its apparent effect on telomeres, the protective caps at the ends of your chromosomes that shorten each time a cell divides and are widely considered one of the body’s built-in aging clocks. In lab studies,, it appears to activate an enzyme called telomerase, which can lengthen telomeres, potentially slowing cellular aging. It also seems to help normalize melatonin production from the pineal gland, which often becomes irregular with age and disrupts sleep.

People use Epitalon hoping for slowed aging, a longer, healthier lifespan, better sleep quality, improved skin and hair, sharper cognition in older age, and stronger immune function. It’s typically given as an injection under the skin in short courses, often 10 to 20 days at a time, repeated once or twice a year, rather than continuously.

The human research base comes almost entirely from Khavinson’s own group in Russia, including some long-running studies in elderly patients that reported reduced mortality over several years, but the work has been criticized for methodological issues and hasn’t been independently replicated outside Russia, so the dramatic anti-aging claims associated with it remain unproven by Western standards.

Melanotan I, also called afamelanotide, is a lab-made peptide based on a natural hormone your body produces called alpha-MSH (alpha-melanocyte-stimulating hormone), which tells the pigment-producing cells in your skin to make more melanin, the brown pigment that causes tanning and helps protect skin from UV damage.

The synthetic version is more stable and longer-lasting than the natural hormone, so a single dose keeps signaling those cells for weeks rather than minutes. Unlike its better-known cousin, Melanotan II, Melanotan I closely mimics the natural hormone’s shape, meaning it mainly affects skin pigmentation without spilling over into the other effects (like nausea, appetite changes, or sexual arousal) that Melanotan II is known for.

Melanotan I is an approved medicine in the United States, Europe, and Australia under the brand name Scenesse, where it’s prescribed for a rare genetic condition called erythropoietic protoporphyria, a disorder that makes sunlight excruciatingly painful within minutes of exposure. By darkening the skin and adding melanin’s natural UV-absorbing protection, Melanotan I lets people with this condition tolerate normal light.

People in peptide therapy circles use it for a deep, lasting tan without prolonged sun exposure, protection against sunburn and UV damage, and, in some cases, improvement in skin conditions like vitiligo where pigmentation has been lost.

Melanotan I is typically given as a small implant placed under the skin that slowly releases the peptide over about 2 months, though injection forms are also available. Melanotan I has one of the most solid human research bases, having undergone full clinical trials and earned formal approval, though only for that one rare condition, not for cosmetic tanning.