Peptide Handbook 2026

Chapter 1. Russian Peptide Science

This chapter tells how Soviet and Russian scientists created peptides that are now studied around the world: Epitalon, Semax, Selank, and the Khavinson bioregulators. It ends with an honest look at the strengths and limitations of the Russian data.

Chapter 2. What Are Peptides: Basic Biochemistry

This chapter explains what peptides are, why most of them can't simply be swallowed, and which routes of administration are used in studies. It also explains how to read the A, B, C, and D evidence levels on the book's cards.

Chapter 3. Anti-Aging Peptides

A chapter on peptides studied as anti-aging agents: they act on the shortening of chromosome ends, mitochondrial fatigue, the buildup of old cells, and the weakening of the immune system. The main idea: one peptide is not enough — you need a well-thought-out combination.

• Epitalon: Epitalon is a short peptide made of four amino acids, created in St. Petersburg in Khavinson's laboratory. It is studied as an agent that may slow cellular aging, support melatonin production, and help regulate daily (circadian) rhythms.
• SS-31: SS-31 (elamipretide) is a small peptide that enters the mitochondria, the cell's "power plants," and strengthens their inner membranes. It is studied for restoring energy production in cells, including in heart and muscle diseases.
• MOTS-c: MOTS-c is a peptide produced by the mitochondria themselves; it is called a "mitochondrial hormone," and its levels decline with age. It is studied as "exercise in a molecule" — for improving sugar metabolism and endurance and for protection against age-related metabolic changes.
• Humanin: Humanin is a peptide encoded in the mitochondria; its level falls with age. It is studied as a protector of nerve cells (including in Alzheimer's disease) and as an agent against cellular insensitivity to insulin.
• FOXO4-DRI: FOXO4-DRI is a "senolytic" peptide that, in mouse experiments, selectively removed old, "stuck" cells without affecting healthy ones. It is studied as a way to rejuvenate tissues by clearing out such cells.
• GHK-Cu: GHK-Cu is a small peptide of three amino acids bound to copper; its blood level drops noticeably with age. It is studied for skin renewal, collagen production, wrinkle reduction, and wound healing.
• Thymalin: Thymalin is a complex of short peptides from the thymus gland that has been used in Russia for more than 40 years. It is studied as an agent for supporting immunity in older adults and extending lifespan, especially together with Epitalon.
• Thymogen: Thymogen is a peptide of just two amino acids, the smallest known immunoactive fragment of the thymus gland. It is studied as a gentle agent for restoring immunity, for example in older patients after cancer surgery.
• Crystagen: Crystagen is a peptide of three amino acids developed in Khavinson's laboratory and taken by mouth. It is studied as an agent for normalizing immunity in older adults.
• Pinealon: Pinealon is a peptide of three amino acids developed in St. Petersburg to support the brain. It is studied as a protector of nerve cells in memory and sleep problems and during recovery from head injuries.
• Vilon: Vilon is a peptide of just two amino acids, created in Khavinson's laboratory to support immunity. It is studied as an agent that helps immune cells survive and cope better with stress; in mice, it extended lifespan.
• AOD-9604: AOD-9604 is a piece of the growth hormone molecule that was studied as a fat-burning agent with no effect on growth. A large human study showed no notable advantage over placebo.
• Cagrilintide: Cagrilintide is a synthetic analog of the hormone amylin that reduces appetite and slows stomach emptying. It is studied for weight loss, especially paired with semaglutide (the drug CagriSema), where some of the best results have been obtained.

Chapter 4. Regeneration and Recovery

This chapter covers peptides studied for wound healing and for restoring muscles, ligaments, cartilage, and immunity after injuries and surgery. Important: BPC-157 and TB-500 have been banned for athletes since 2022, and for most of these substances there are still few reliable human studies.

• BPC-157: BPC-157 is a peptide made of 15 amino acids, a fragment of a protein found in human gastric juice. It is studied as a substance that may speed up healing of the stomach, intestines, muscles, and ligaments, but there are almost no human studies yet.
• TB-500: TB-500 is a short synthetic piece of the natural protein thymosin beta-4. It is studied for tissue recovery after sports injuries, but it has no human studies of its own — all data were obtained for the full protein.
• GHK-Cu: GHK-Cu is a small peptide of three amino acids bound to copper; it is found in human blood, and its levels decline with age. It is studied as a signal for renewing skin and tissues: collagen production, blood vessel growth, and reduced inflammation.
• LL-37: LL-37 is the only peptide of its family that the human body produces itself to defend against microbes. It is studied as a means against resistant bacteria and for healing chronic wounds.
• Thymalin: Thymalin is a mixture of short peptides from the thymus gland of cattle. In the context of recovery, it is studied as a support for immunity during wound healing and after surgery.
• Thymogen: Thymogen is a very short peptide of just two amino acids. It is studied as a gentle means of restoring immunity after injuries and surgery.
• Cartalax: Cartalax is a short peptide of three amino acids created in Khavinson's laboratory for cartilage tissue. It is studied as a substance that may support joint cartilage, but so far only in cell experiments.

Chapter 5. Metabolism and Body Composition

A chapter about substances studied for weight loss and better metabolism. The main characters are copies of gut-made satiety hormones, which in recent years have made 15–24% weight loss possible, alongside agents for fat burning and for supporting the liver, muscles, and bones.

• Semaglutide: Semaglutide is a copy of a natural satiety hormone made in the gut. It is studied for weight loss and heart protection; in large studies, people lost about 15% of their body weight.
• Tirzepatide: Tirzepatide acts like two gut satiety hormones at once. It is studied for weight loss and type 2 diabetes; in studies, weight loss reached 22.5%, almost as much as after stomach surgery.
• Liraglutide: Liraglutide was the first satiety-hormone copy approved for treating obesity. It is weaker than newer analogs and is given every day, but it has been studied for more than ten years.
• Retatrutide: Retatrutide acts like three hormones at once that control appetite and fat burning. In studies it showed record weight loss — more than 24% — and greatly reduced liver fat, but it is not yet approved anywhere.
• Cagrilintide: Cagrilintide is a copy of the hormone amylin, which helps you feel full. Paired with semaglutide in a single injection, it is studied for weight loss; in a large study, the combination produced about 20% weight loss.
• Survodutide: Survodutide acts like two hormones — a satiety hormone and glucagon, which makes the liver burn fat. It is studied mainly in fatty liver disease; in a study, liver inflammation resolved in most participants.
• Mazdutide: Mazdutide is a Chinese drug that, like survodutide, acts as both a satiety hormone and glucagon. In a Chinese study, people lost up to 17.6% of their weight in a year.
• Tesamorelin: Tesamorelin makes the pituitary gland release the body's own growth hormone. It is approved for reducing fat around the internal organs in people with HIV and is also being studied in fatty liver disease and memory decline.
• Fragment 176-191: Fragment 176-191 is a small piece of the growth hormone molecule that is responsible for breaking down fat but does not affect growth or blood sugar. It was studied as a weight-loss agent, but a large human study showed no effect.
• 5-Amino-1MQ: 5-Amino-1MQ is not a peptide but a small molecule that keeps cells from losing NAD+, a substance important for energy. It is being studied in animals as an agent against obesity and muscle loss; there are no human data.
• Tesofensine: Tesofensine is not a peptide but a substance that raises levels of serotonin, norepinephrine, and dopamine in the brain and thereby reduces appetite. It is being studied for weight loss; it was originally developed for Parkinson's disease.
• Lipo-B: Lipo-B is not a peptide but a mixture of methionine, inositol, choline, and vitamin B12 that is used to support fat metabolism in the liver. It is used in American weight-loss clinics, but it has not been studied as a single formula: only the individual components have been studied, and the effect…
• L-Carnitine / Lipo-C: L-carnitine is a substance that carries fatty acids into the cell's "power plants," where they are burned. It is being studied for weight loss, recovery after exercise, and nerve damage; its effect on weight is small — about one kilogram.
• NAD+/NMN: NMN is not a peptide but a precursor of NAD+, a key molecule for energy production in cells, whose supply declines with age. It is being studied as a way to improve insulin sensitivity and endurance and to slow aging.
• Glutathione: Glutathione is a short peptide made of three amino acids and the cell's main defender against oxidative damage. It is being studied as an antioxidant involved in neutralizing toxins and in immune function.
• Calcitonin: Calcitonin is a hormone that slows the breakdown of bone; the salmon version is dozens of times more active than the human one. It is approved for osteoporosis and Paget's disease, and in studies it reduced pain from vertebral compression fractures.

Chapter 6. Growth Hormone Axis Peptides (GH Axis)

As we age, the body makes less and less growth hormone, which affects muscle, fat, recovery, and sleep. This chapter covers peptides that are being studied as a way to gently nudge the pituitary gland into releasing its own growth hormone, as well as IGF-1 itself, the substance through which growth hormone acts on tissues.

• CJC-1295 DAC: CJC-1295 with DAC is a man-made copy of a natural signal that tells the pituitary gland to release growth hormone. Because it attaches to a blood protein, it works for almost a week, so it is studied as an option that needs only infrequent doses.
• Mod-GRF(1-29): Mod-GRF(1-29) is a reinforced version of sermorelin, a short signal for the pituitary gland. It is studied as a way to trigger natural short bursts of growth hormone, especially when paired with ipamorelin.
• Sermorelin: Sermorelin is the starting piece of a natural hormone that "wakes up" the pituitary gland and makes it release its own growth hormone. It is studied in older adults for preserving muscle mass and immunity.
• Ipamorelin: Ipamorelin is a short man-made peptide of five amino acids that nudges the pituitary gland to release growth hormone. Researchers value it for its selectivity: it barely raises stress hormones.
• GHRP-2: GHRP-2 is a man-made peptide of six amino acids that boosts growth hormone release through the "hunger hormone" receptor. In Japan it is used as a diagnostic test for growth hormone deficiency.
• GHRP-6: GHRP-6 was the first man-made peptide shown to boost growth hormone release; it also strongly stimulates appetite. It is studied in wasting conditions, and Cuban scientists study it for protecting the heart and healing wounds.
• Hexarelin: Hexarelin is one of the most potent man-made peptides that boost growth hormone release. Its ability to protect heart muscle is of special interest, but so far this has only been shown in mice.
• MK-677: MK-677 (ibutamoren) is not a peptide but a small molecule taken as a pill that mimics the "hunger hormone" and increases growth hormone production. It has been studied for years: it increased muscle mass and improved deep sleep, but it can raise blood sugar.
• IGF-1: IGF-1 (mecasermin) is the protein through which growth hormone acts on tissues; its recombinant version is approved as a drug. It is used for severe primary IGF-1 deficiency, when the body does not respond to growth hormone, and is being studied in Rett syndrome.
• IGF-1 LR3: IGF-1 LR3 is a modified man-made form of IGF-1 that stays active in the blood longer. It is studied in animals as a strong stimulator of tissue growth and a protector of nerve cells, but there have been no human trials.

Chapter 7. Neuroprotection and Cognitive Function

This chapter covers peptides studied for protecting the brain, improving memory and attention, reducing anxiety, and restoring healthy sleep. Here, compounds with many years of use (Semax, Selank, Cortexin, Cerebrolysin) sit side by side with experimental molecules that have so far been tested only in animals.

• Semax: Semax is a Russian peptide drug based on a fragment of a pituitary hormone; it is given as nose drops. It is studied as a way to protect the brain after a stroke and to improve attention and memory.
• Selank: Selank is a Russian peptide given as nose drops; it is registered as an anti-anxiety drug. It is studied as a way to reduce anxiety without drowsiness or dependence and to gently improve attention.
• Cerebrolysin: Cerebrolysin is a drug made from pig brain peptides, registered in more than 50 countries. It is studied in stroke, Alzheimer's disease, and traumatic brain injury as a way to help nerve cells survive and recover.
• Cortexin: Cortexin is a Russian drug made from peptides of the animal cerebral cortex. It is studied in stroke, head injuries, and pediatric neurology as a way to protect nerve cells.
• Noopept: Noopept is a Russian nootropic, a small peptide-like molecule taken by mouth or under the tongue. It is studied as a way to improve memory and speed of thinking, including in age-related and vascular impairments.
• Humanin: Humanin is a small peptide made by mitochondria, the "power plants" of cells; its levels decline with age. It is studied as protection for nerve cells in Alzheimer's disease and in metabolic disorders, so far only in laboratory experiments.
• Pinealon: Pinealon is a very short peptide of three amino acids, a brain bioregulator from Khavinson's school. It is studied as a way to support nerve cells in age-related memory decline, sleep disorders, and after head injuries.
• DSIP: DSIP is a small peptide discovered in 1977 that is linked to deep sleep. It is studied as something that does not force sleep but helps restore normal sleep, and also in opioid withdrawal and chronic pain.
• VIP: VIP is a natural 28-amino-acid peptide that reduces inflammation and widens the airways; its drug form is called aviptadil. It has been studied in severe lung damage from coronavirus infection, in pulmonary hypertension, and for protecting nerve tissue.
• ACTH(4-10): ACTH(4-10) is a short fragment of a pituitary hormone that has no hormonal action; Semax was created on its basis. It has been studied since the 1970s as a way to improve attention and memory.
• Adamax: Adamax is a modified version of Semax with protected molecule ends, marketed as a “boosted Semax.” There are no scientific publications on it; all data are taken from regular Semax.
• Dihexa: Dihexa is a small, stable molecule resembling a fragment of the hormone angiotensin that enters the brain and works when taken by mouth. It is studied in animals as a substance that stimulates the formation of new connections between nerve cells, including in models of Alzheimer's disease.
• ARA-290: ARA-290 (cibinetide) is a peptide derived from the hormone erythropoietin but without its effect on blood. It was studied in two clinical trials in small-nerve damage, where it improved the condition of nerve fibers and reduced symptoms.
• PE-22-28: PE-22-28 is a short peptide of seven amino acids, a shortened version of the natural peptide spadin. It is studied in animals as a possible fast-acting agent against depression.
• P-21 / P021: P-21 is a short peptide of six amino acids created on the basis of a natural nerve cell growth factor; it enters the brain and works when taken by mouth. It is studied in mice as an agent against brain changes in Alzheimer's disease, Down syndrome, and a rare form of epilepsy.

Chapter 8. The Immune System

A chapter on peptides studied for immune support: hormones of the thymus gland, which almost disappears with age, and the natural "antibiotics" of the skin and mucous membranes. Fragments studied for tissue healing are described separately.

• Thymalin: Thymalin is a mixture of short protein fragments obtained from the thymus gland of cattle. It is studied as an agent that may restore immunity weakened by age; in a long-term follow-up of older adults, mortality was about half as high.
• Thymosin Alpha-1: Thymosin alpha-1 is a natural 28-amino-acid hormone of the thymus gland, sold as the drug Zadaxin in many countries. It is studied as an agent that helps the immune system fight infections and tumors while also calming excessive inflammation.
• Thymosin Beta-4: Thymosin beta-4 is a natural 43-amino-acid protein that helps cells move to the site of injury. It is studied for tissue healing: repair of heart muscle and blood vessels, and in eye drops for severe dry eye.
• TB-500: TB-500 is a short synthetic piece of the thymosin beta-4 protein, designed to mimic its ability to help cells move to the site of injury. It is studied for recovery of muscles, tendons, and joints, but it has no clinical studies of its own.
• Thymogen: Thymogen is a peptide made of just two amino acids, isolated from the thymus gland as its smallest immunologically active fragment. It is studied as a gentle agent for restoring immunity, for example in older adults after surgery.
• Vladonix: Vladonix is a thymus peptide complex similar to Thymalin, but in capsules taken by mouth. It is studied as a course-based agent to support immunity that weakens with age.
• LL-37: LL-37 is the body's own protective peptide, produced in the skin and mucous membranes, that destroys bacteria, viruses, and fungi. It is studied for healing chronic wounds, for acne and rosacea, and for fighting resistant bacteria.
• Defensins: Defensins are a large family of natural protective peptides that are the first to meet microbes on the skin, in the gut, and on other mucous membranes. They are studied as a basis for anti-infection creams and as vaccine helpers.

Chapter 9. Cosmetology and Skin Health

A chapter on peptides for the skin: some temporarily relax the facial expression muscles, others help the skin produce collagen, and still others lighten dark spots or, on the contrary, boost protective pigment. Most of them are cosmetic ingredients for creams, and one is a prescription drug.

• Argireline: Argireline is a short peptide made of six amino acids that is added to creams and serums. It is studied as a "peptide Botox": an ingredient that temporarily relaxes the facial expression muscles and reduces wrinkles.
• Leuphasyl: Leuphasyl is a cosmetic peptide made of five amino acids that resembles the body's own natural painkilling substances. It is studied as a cream ingredient that relaxes the facial expression muscles and reduces wrinkles, especially together with Argireline.
• Matrixyl: Matrixyl is one of the most studied cosmetic peptides — a small piece of the collagen precursor molecule. It is studied as an ingredient that nudges the skin to produce new collagen and makes wrinkles shallower.
• SNAP-8: SNAP-8 is a longer, eight-amino-acid version of Argireline for cosmetics. It is studied as an ingredient that relaxes the facial expression muscles more strongly and reduces wrinkles at a lower concentration.
• Melanostatin: Melanostatin is a nine-amino-acid peptide for creams that interferes with the skin's production of pigment. It is studied as a gentle ingredient for lightening dark spots that does not damage pigment cells.
• Melanotan I: Melanotan I (afamelanotide) is a peptide drug approved in the US and Europe that makes the skin produce protective dark pigment without sun exposure. It is used for a rare disease involving intolerance to light and is being studied in vitiligo.

Chapter 10. Reproductive Health

This chapter covers peptides that affect the reproductive system and sexual desire through brain hormones. Most of them are approved prescription drugs used only under a doctor's supervision; others are being studied in research or have almost no scientific data.

• Gonadorelin: Gonadorelin is an exact copy of a natural brain hormone that switches on the sex glands. Doctors use it to test the hormone system and to restore sperm production when the body's own hormones are lacking.
• Triptorelin: Triptorelin is an enhanced, long-acting version of the brain hormone that controls the sex glands. It is an approved drug: with continuous administration, it temporarily "switches off" sex hormone production, which is used in prostate cancer, endometriosis, and puberty that starts too early.
• PT-141: PT-141 (bremelanotide) is a ring-shaped peptide approved in the U.S. as a medicine for women with low sexual desire. It works through the brain rather than the blood vessels, and it is being studied as a way to enhance desire.
• Kisspeptin: Kisspeptin is a natural "gatekeeper" peptide that switches on the brain's reproductive hormone axis. It is being studied for triggering ovulation in IVF, for menstrual cycle disorders, and for low sexual desire.
• Testoluten: Testoluten is a complex of short peptides from the testes of young animals, developed by the Khavinson school. It is considered a support for testicular function, but there are no direct scientific publications about it.
• Oxytocin: Oxytocin is the brain's own hormone, often called the "bonding hormone." As a nasal spray, it is being studied as a way to increase trust and emotional closeness and to reduce social anxiety.

Chapter 11. BioPeptidePlus Longevity Protocols

This chapter brings together 15 ready-made schemes in which several peptides and supplements are combined for a single goal — rejuvenation, sleep, immunity, weight loss, and others. The idea is that the mechanisms of aging are linked to one another, so each scheme acts on several of them at once.

Chapter 12. Practical Application

This chapter is about how peptides are handled in research: how the powder is turned into a solution, how it is stored and administered, why breaks are taken between courses, and which lab tests are monitored. Common mistakes that cause a peptide to spoil or become dangerous are covered separately.

Chapter 13. Safety and Contraindications

A chapter about risks: in which conditions peptides must not be used, which drugs they can be dangerously — even life-threateningly — combined with, and what is actually known about the link between peptides and cancer. It also covers legal status in Russia and worldwide, the list of substances banned for athletes, an honest look at molecules with weak evidence, and the signs of a counterfeit peptide.

Research protocols

• Protocol I: Cellular Reset — A three-month program that first studies clearing the body of aged cells, then restoring the cell's "power plants" and protecting the ends of chromosomes. It is viewed as a systematic approach to slowing aging after 40.
• Protocol II: Hormonal Balance — A six-week program with Khavinson bioregulator peptides for the adrenal glands, the pineal gland, and the sex glands. It is studied in chronic fatigue, low sex drive, and age-related hormonal changes.
• Protocol III: Brain Energy — A program of peptides studied for clear thinking, memory, and reduced anxiety. There is a basic version for "brain fog" and burnout, and an enhanced one for post-COVID and more serious impairments, only under a neurologist's supervision.
• Protocol IV: Resetting the Biological Clock — A three-month program for people over 50 whose biological age is noticeably ahead of their chronological age. It studies clearing out old cells, restoring cellular energy, and supporting the immune system, and the result is assessed with an "epigenetic clock" test.
• Protocol V: Immune Fortress — A thirty-day regimen for people over 45 who catch colds often or have been left weakened after COVID. It studies peptides that may restore the thymus gland and strengthen the body's own defenses before cold season.
• Protocol VI: Physical Recovery — A six-week regimen for recreational athletes and people recovering from ligament, tendon, and muscle injuries. The peptides in it are studied as agents that may speed up tissue healing and the return to training; some of them are banned in professional sports.
• Protocol VII: Women's Regeneration — An eight-week regimen for women over 45 in the years before and after menopause. The peptides in it are studied as support for sleep, skin, mood, and immunity and as a way to reduce hot flashes; it does not replace hormone therapy when symptoms are severe.
• Protocol VIII: Detox and Renewal — A thirty-day plan to support the liver, for example in fatty liver disease or after COVID. The word "detox" is used loosely here: researchers study how a liver peptide bioregulator and supplements may support liver cells and their recovery.
• Protocol IX: Maintenance Cycle — A yearly plan of four short seasonal courses for people who have already completed one of the main protocols. Spring focuses on renewal, summer on energy, fall on immunity, and winter on cell protection and mood.
• Protocol X: Vascular Health — A protocol on supporting blood vessels in people over 50 with high blood pressure and atherosclerosis. It studied a combination of vascular-wall peptide bioregulators and the peptide BPC-157 together with diet and walking.
• Protocol XI: Strong Skeleton — A protocol on supporting bones and joints in people over 50 with osteoporosis and chronic joint pain. It studied cartilage and bone bioregulators together with tissue-repair peptides, calcium, and vitamin D.
• Protocol XII: Deep Sleep — A protocol on restoring deep sleep in chronic insomnia, jet lag, and age-related sleep problems. It studied delta sleep-inducing peptide together with bioregulators linked to the body's own melatonin production.
• Protocol XIII: Clear Vision — A protocol on supporting vision in people over 55 with early age-related changes in the retina and worsening vision at dusk. It studied peptide bioregulators of the retina and optic nerve together with eye vitamins.
• Protocol XIV: Metabolic Synergy / NAD+ Link — A three-month protocol on restoring cellular energy in people over 40 who feel run down and recover slowly after exercise. It studied a combination of precursors of the NAD+ molecule with the mitochondrial peptides SS-31 and MOTS-c.
• Protocol XV: Smart Weight Loss — A step-by-step weight-loss scheme for obesity: first, vitamin and mineral deficiencies are corrected; then appetite reduction with tirzepatide or retatrutide is studied; after that, they are gradually tapered off and the result is consolidated. The main idea is to lose fat, not muscle, so body…

Appendices

• Appendix A. Scientific Basis: PubMed Articles by Chapter
• Appendix B. Peptide Synergy Matrix
• Appendix C. Dosage Summary Table
• Appendix D. Glossary of Terms
• Appendix E. Abbreviations
• Appendix F. Monitoring Templates
• Appendix G. Legal Status and WADA