Peptides for Anxiety and Depression – Semax, Selank, Oxytocin

Peptides for Anxiety and Depression – Semax, Selank, Oxytocin

Peptides are the building blocks of protein and act as modulators for different receptors and molecules in the body. You can think of them like messengers that help control the switchboard functions of every system in our body. They are made from groups of amino acids bound together by peptide bonds, and there are over 7,000 types of peptides in every one of us. They all do specific things but overall, a peptide’s role is to “allow the body’s innate immune system to do its job of protecting against invaders and efficiently maintain health and homeostasis” (Seeds, 2020). While you may not have heard of peptides before, you definitely know the most popular peptide in the world: insulin! Yes, insulin is a peptide that most of us make naturally in our body to regulate blood sugar. For those who do not make it endogenously (on our own, inside our body), such as those with diabetes, they can get it exogenously (outside the body) via insulin shots. This was such an important discovery, that the scientists who discovered this were awarded the Nobel Prize for medicine in 1923. There are currently over 60 peptides approved by the FDA as medicines, and hundreds more being studied in clinical trials. Their potency, tolerability, and ease of use make them great options to maintain health and wellness and help deal with illness and disease.

Anxiety and depression are two of the most common conditions in America, and the rates of those who experience them are growing at an alarming rate. According to The Washington Post, “A third of Americans now show signs of clinical anxiety or depression,” with rates the highest for young adults, women, and those experiencing poverty (Fowers, & Wan, 2020).The most common drugs used to treat the types of anxiety depression are Benzodiazepines, Selective Serotonin Reuptake Inhibitors (SSRI), Serotonin and Norepinephrine Reuptake Inhibitors (SNRI), Tricyclic and Tetracyclic Antidepressants, Atypical Antidepressant, Monoamine Oxidase Inhibitors (MAOIs), N-methyl D-aspartate (NMDA) Antagonist. Side effects of these drugs can include physical dependence, amnesia, birth defects, nausea, insomnia and sexual dysfunction, suicidal ideation, and many more. There are many holistic options that can help treat anxiety and depression and have little to no side effects, are gentle on the body, and empower individuals to nurture their health and states of mind. They can be used in place of or alongside or pharmacological treatment, depending on guidance from your healthcare provider. One of these modalities that can greatly help independently or as an adjunctive therapy is peptides.

Semax, also known as N-Acetyl, is a synthetic peptide derived from a fragment of adrenocorticotropic hormone (ACTH), which is naturally produced in the pituitary gland. It consists of a sequence of amino acids and primarily acts on the central nervous system where it enhances the levels of various neurotransmitters, including dopamine, serotonin, and norepinephrine (the main chemicals that control our mood). It also promotes the production of brain-derived neurotrophic factor (BDNF), which is involved in neuronal growth and repair and is “neuroprotective and contributes to mitochondrial stability under stress” (Seeds, 2020). This helps us mentally rebound from stressful events, and deal with them more easily when they initially occur. In the study “Effects of Semax on the Default Mode Network of the Brain,” Lebedeva et al. (2018) showed that there was increased activation in the brain’s default mode network, responsible for focus and memory processing, for the group that took Semax based on functional magnetic resonance imaging, or fMRI, a type of brain scan.  Clinical studies have also shown that it affects several biological processes, most notably the immune system. As reported by Medvedev et al. (2014), “Semax altered the expression of genes that modulate the amount and mobility of immune cells and enhanced the expression of genes that encode chemokines and immunoglobulins.” Since Semax helps to regulate hormones and neurotransmitters, acts as a neuroprotective, helps with mitochondrial stability, memory and immunity, it is an excellent option to assist with mental health. 

Selank is also another synthetic peptide that is similar in structure to the naturally occurring neuropeptide tuftsin. Research suggests that Selank’s anti-anxiety properties are due to the fact that it modulates the levels of certain neurotransmitters in the brain, such as serotonin, dopamine, and GABA. Its anti-anxiety properties are significant and: “clinical studies have shown that Selank had an anxiolytic effect comparable to that of classical benzodiazepine drugs” (Filatova, et al., 2017). Selnak has also been shown to “decrease the rate at which enkephalins [peptides made by the body involved in regulating pain sensation] are degraded, which consequently decreases the anxiety response in humans.” Dr. Seeds (2020) notes: “On top of its antianxiety, antidepressant, and antiasthenic properties, it can also enhance memory and cognitive function” and (Volkova et al., 2016) found that “ Selank also has a nootropic action, which positively influences the formation of memory and learning processes, and marked immunomodulatory activity.” The mental health benefits of this peptide are clear, and many times both Selank and Semax are used as a combined therapy since they work so well together.

Oxytocin is a neurotransmitter that everyone has heard of, usually in reference to it being the “love hormone” since it is “associated with trust, sexual arousal and relationship building” (Cleveland Clinic, 2022). The hypothalamus in our brain makes oxytocin and then our pituitary gland stores and releases it into our bloodstream, where it plays a role in regulating social behavior, emotions, and stress responses. Studies have suggested that individuals with anxiety and depression may have altered oxytocin levels or oxytocin receptor functioning (Cochran et al, 2013). By administering oxytocin as a therapeutic intervention, the aim is to modulate and potentially alleviate symptoms of anxiety and depression. Oxytocin has several effects that contribute to its potential therapeutic benefits, including anxiety reduction, social bonding /support, trust and empathy, and emotion regulation.

While there are many helpful peptides available, Semax, Selank, and Oxytocin used alone or in combination are a great natural therapy to help with common mental health struggles and the daily stressors in life.


Cleveland Clinic. (2022, March 27). Oxytocin: What it is, Function & Effects. Oxytocin.,male%20and%20female%20reproductive%20systems.

Cochran, D. M., Fallon, D., Hill, M., & Frazier, J. A. (2013). The role of oxytocin in psychiatric disorders: a review of biological and therapeutic research findings. Harvard review of psychiatry, 21(5), 219–247.

Fowers, A., & Wan, W. (2020, May 26). A third of Americans now show signs of clinical anxiety or depression, Census Bureau finds amid coronavirus pandemic. Retrieved May 14, 2023, from

Filatova, E., Kasian, A., Kolomin, T., Rybalkina, E., Alieva, A., Andreeva, L., Limborska, S., Myasoedov, N., Pavlova, G., Slominsky, P., & Shadrina, M. (2017). GABA, Selank, and Olanzapine Affect the Expression of Genes Involved in GABAergic Neurotransmission in IMR-32 Cells. Frontiers in pharmacology, 8, 89.

Glazova, N.Y., Sebentsova, E.A., Manchenko, D.M. et al. The Protective Effect of Semax in a Model of Stress-Induced Impairment of Memory and Behavior in White Rats. Biol Bull Russ Acad Sci 45, 394–399 (2018).

Lebedeva, I. S., Panikratova, Y. R., Sokolov, O. Y., Kupriyanov, D. A., Rumshiskaya, A. D., Kost, N. V., & Myasoedov, N. F. (2018). Effects of Semax on the Default Mode Network of the Brain. Bulletin of experimental biology and medicine, 165(5), 653–656.

Medvedeva, E. V., Dmitrieva, V. G., Povarova, O. V., Limborska, S. A., Skvortsova, V. I., Myasoedov, N. F., & Dergunova, L. V. (2014). The peptide semax affects the expression of genes related to the immune and vascular systems in rat brain focal ischemia: genome-wide transcriptional analysis. BMC genomics, 15, 228.

Medvedev, V. E., Tereshchenko, O. N., Kost, N. V., Ter-Israelyan, A. Y., Gushanskaya, E. V., Chobanu, I. K., Sokolov, O. Y., & Myasoedov, N. F. (2015).Optimization of the treatment of anxiety disorders with selank. Journal of Neurology and Psychiatry, 115(6), 33–40.

Seeds, W. A. (2020). The peptide protocols: A handbook for practitioners. Spire Institute.

Volkova, A., Shadrina, M., Kolomin, T., Andreeva, L., Limborska, S., Myasoedov, N., & Slominsky, P. (2016). Selank Administration Affects the Expression of Some Genes Involved in GABAergic Neurotransmission. Frontiers in pharmacology, 7, 31.

About the author: Mary Genevieve Carty, MS, MHEd holds Masters degrees in Complementary and Integrative Health as well as Higher Education and is currently a doctoral student in Health Science at George Washington University’s College of Medicine and Health Science.  She is passionate about holistic health and wellness, and has additional training in teaching, Reiki, and Tapping/ Emotional Freedom Technique. Her research interests include resiliency, psychoneuroimmunology, neuroplastic pain, placebo/ nocebo effect, and bioenergy therapies.  The views she expresses are her own, and do not reflect any affiliation.

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Medically reviewed by Dr. Stephen Matta, DO, MBA CAQSM and Mary Anne Matta, MS, MA, LAC

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