Semax is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2025-10-15. Where a claim depends on a specific study, the study is described rather than over-claimed.
The parent fragment ACTH(4-10) carries the sequence Met-Glu-His-Phe-Arg-Trp-Gly. Semax replaces the arginine and tryptophan positions with a proline-glycine-proline tail, giving Met-Glu-His-Phe-Pro-Gly-Pro. That change removes residues associated with adrenal stimulation, so the peptide does not drive cortisol release the way full ACTH does. This distinction shapes how the compound is grouped in the literature, where it sits with neuropeptides and peptide neuromodulators rather than with corticosteroids.
Regulatory status varies sharply by country. Semax is registered for medical use in Russia, where it appears in formularies as a nasal solution, and it also holds registration in a small number of neighbouring states. It has no approval from the United States Food and Drug Administration or the European Medicines Agency, and it is not a scheduled controlled substance in most jurisdictions. Elsewhere it circulates mainly as laboratory material, so purity documentation comes from suppliers rather than from a national pharmacopoeia.
Scientific literature on semax is unevenly distributed. A substantial share of published work originates from a small number of laboratories in Russia, while independent replication elsewhere is limited. Human data consist mostly of small trials with short follow-up, and several reported outcomes rely on subjective rating scales. Questions about how much intact peptide reaches the central nervous system after nasal administration, and how long it persists there, are still unresolved. The compound is best described as an active research subject rather than a settled pharmacological agent.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It was derived from the ACTH(4-10) fragment, a short segment of adrenocorticotropic hormone that lacks the hormonal activity associated with the full-length peptide. Researchers at the Institute of Molecular Genetics in Moscow developed the compound during the 1980s. It has been registered as a pharmaceutical product in Russia and several neighbouring countries, where it is supplied as a nasal solution, and it is also sold internationally as a research chemical.
The proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Analogue of the ACTH(4-10) fragment |
| Amino acid sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Single-letter form MEHFPGP |
| Molecular formula | C37H51N9O10S | Free peptide, nominal mass near 814 Da |
| First registration | 1994, Russia | Nasal formulation for neurological indications |
| Typical purity grade | 95% or higher by HPLC | Research material; higher grades used as reference standards |
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
The C-terminal Pro-Gly-Pro extension is not incidental. Proline-rich tails are known to resist several common peptidases, and the published literature attributes the longer half-life of Semax, relative to unmodified ACTH fragments, to this feature. The modification also removes the melanocyte-stimulating and corticosteroidogenic activity that characterizes longer ACTH-derived sequences. Because the molecule is small and hydrophilic, it is typically formulated as an aqueous solution for intranasal or parenteral delivery. Acetylation or amidation at the termini appears in closely related research peptides and shifts the mass by a fixed increment.
After earning his doctorate in biochemistry, Lehninger held various faculty positions at the University of Wisconsin–Madison and the University of Chicago. In 1952, he went to the Johns Hopkins School of Medicine, assuming the title of DeLamar Professor of the Department of Biological Chemistry. He served in this position until 1978, when he was appointed to the role of University Professor of Medical Sciences. He held this title until his death in 1986. 1948 – Paul-Lewis Award in Enzyme Chemistry 1951 – Guggenheim Fellowship 1956 – Elected to the National Academy of Sciences 1959 – Elected to the American Academy of Arts and Sciences 1969 – Remsen Award of the American Chemical Society 1970 – American Philosophical Society 1986 – Passano Foundation Award Forthcoming in New Dictionary of Scientific Biography
In 2013, during the Long Shutdown 1, three ISOLDE buildings were demolished. They've been built again as a new single building with a new control room, a data storage room, three laser laboratories, a biology and materials laboratory, and a room for visitors. Another building extension for the MEDICIS project and several others equipped with electrical, cooling and ventilation systems to be used for the HIE-ISOLDE project in the future were also built. In addition, the robots which were installed for the handling of radioactive targets have been replaced with more modern robots. In 2015, for the first time, a radioactive isotope beam could be accelerated to an energy level of 4.3 MeV per nucleon in the ISOLDE facility thanks to the HIE-ISOLDE upgrades. In late 2017, the CERN-MEDICIS facility produced its first radioisotopes and by the end of 2020 had provided external nine hospitals and research facilities with 41 batches of radioisotopes. Phase 2 of the facility's HIE-ISOLDE upgrade was completed in 2018, which allows ISOLDE to accelerate radioactive beams up to 10 MeV per nucleon.
=== 1989 Kramatorsk, Ukraine === The 1989 Kramatorsk incident happened in 1989 when a small capsule 8 by 4 millimetres (0.3 by 0.2 inches) in size of caesium-137 was found inside the concrete wall of an apartment building in Kramatorsk, Ukrainian SSR. It is believed that the capsule, originally a part of a measurement device, was lost in the late 1970s and ended up mixed with gravel used to construct the building in 1980. Over 9 years, two families had lived in the apartment. By the time the capsule was discovered, 6 residents of the building had died, 4 from leukemia and 17 more receiving varying doses of radiation.
== Further reading == Davidson JA, Sloan L (January 2017). "Fixed-Dose Combination of Canagliflozin and Metformin for the Treatment of Type 2 Diabetes: An Overview". Adv Ther. 34 (1): 41–59. doi:10.1007/s12325-016-0434-2. PMC 5216068. PMID 27854055.
Ghana, officially the Republic of Ghana, is a country in West Africa. It is situated with the Gulf of Guinea and the Atlantic Ocean to the south, and shares borders with Ivory Coast to the west, Burkina Faso to the north, and Togo to the east. Ghana covers an area of 239,567 km2 (92,497 sq mi), spanning various ecologies, from coastal savannas to tropical rainforests. With over 35 million inhabitants, Ghana is the thirteenth-most populous country in Africa, and the second-most populous country in West Africa. The capital and most populous city is Accra. The earliest kingdoms to emerge in Ghana were Bonoman in the south and the Kingdom of Dagbon in the north, with Bonoman existing in the area during the 11th century. The Asante Empire and other Akan kingdoms in the south emerged over the centuries. Beginning in the 15th century, the Portuguese Empire, followed by other European powers, contested the area for trading rights, until the British ultimately established control of the coast by the 19th century. Following more than a century of colonial resistance, the later borders of the country took shape, encompassing four separate British colonial territories: Gold Coast, Ashanti, the Northern Territories, and British Togoland. These were unified as an independent dominion within the Commonwealth of Nations. On 6 March 1957, Ghana became the first colony in Sub-Saharan Africa to achieve sovereignty. Under President Kwame Nkrumah, it became influential in decolonisation efforts and the Pan-African movement.
Sources: en.wikipedia.org
=== Physiological factors === Physiological changes in nursing women, including an unusual milk supply and blocked milk ducts, cause nipple or breast ache. An oversupply of breast milk is caused by overactive milk expression. Hence, the excess milk accumulates, leading to breast engorgement and pain. On the other hand, milk supply will be lowered by prolonged breastfeeding, high pumping pressure and overly vigorous breast massage. Blocked milk ducts refers to lactiferous ducts' blockage at the nipple pore or deeper breast tissue. It hampers an adequate drainage of milk and causes breast mass, engorgement, redness, a nipple bleb and subsequent pain.
== Consumerism == Historians debate whether the spread of American-style consumerism to Western Europe (and Japan) was part of the Cold War. Steigerwald reviews the debate by looking at the book Trams or Tailfins? Public and Private Prosperity in Postwar West Germany and the United States (2012) by Jan L. Logemann:
From a biological standpoint, water has many distinct properties that are critical for the proliferation of life. It carries out this role by allowing organic compounds to react in ways that ultimately allow replication. All known forms of life depend on water. Water is vital both as a solvent in which many of the body's solutes dissolve and as an essential part of many metabolic processes within the body. Metabolism is the sum total of anabolism and catabolism. In anabolism, water is removed from molecules (through energy requiring enzymatic chemical reactions) to grow larger molecules (e.g., starches, triglycerides, and proteins for storage of fuels and information). In catabolism, water is used to break bonds to generate smaller molecules (e.g., glucose, fatty acids, and amino acids to be used for fuels for energy use or other purposes). Without water, these particular metabolic processes could not exist. Water is fundamental to both photosynthesis and respiration. Photosynthetic cells use the sun's energy to split off water's hydrogen from oxygen. In the presence of sunlight, hydrogen is combined with CO2 (absorbed from air or water) to form glucose and release oxygen. All living cells use such fuels and oxidize the hydrogen and carbon to capture the sun's energy and reform water and CO2 in the process (cellular respiration). Water is also central to acid-base neutrality and enzyme function. An acid, a hydrogen ion (H+, that is, a proton) donor, can be neutralized by a base, a proton acceptor such as a hydroxide ion (OH−) to form water.
A mismatch between the circadian rhythm and the meals schedule, such as in circadian rhythm disorders, may increase insulin resistance. Insufficient sleep has been shown to cause insulin resistance, and also increases the risk of developing metabolic diseases such as type 2 diabetes and obesity.
Sources: en.wikipedia.org
=== Affinity chromatography === Affinity chromatography emerged in the 1950s as a rarely used method used to purify enzymes; it has since seen mainstream use and is the oldest among chemoproteomic approaches. Affinity chromatography is performed following one of two basic formats: ligand immobilization or target immobilization. Under the ligand immobilization format, a ligand of interest - often a drug lead - is immobilized within a chromatography column and acts as the stationary phase. A complex sample consisting of many proteins, such as a cell lysate, is passed through the column and the target of interest binds to the immobilized ligand while other sample components pass through the column unretained. Under the target immobilization format, a target of interest - often a disease-relevant protein - is immobilized within a chromatography column and acts as the stationary phase. Pooled compound libraries are then passed through the column in an application buffer, ligands are retained through binding interactions with the stationary phase, and other compounds pass through the column unretained. In both cases, retained analytes can be eluted from the column and identified using mass spectrometry. A table of elution strategies is provided below.
For example in the E1 transition, unless Δ l = ± 1, Δ ml = 0 or ± 1, Δ ms = 0, and Δ n = any integer, the equation above will yield a value equal to zero and the transition would be known as a “forbidden transition”. For example, this would occur for certain cases like when Δ l = 2. In this case, the transition would not be allowed and therefore would be much weaker than an allowed transition. These specific values for the changes in quantum numbers are known as the selection rules for the allowed transitions and are shown for common transitions in the table below:
=== Systems Pharmacology === Systems Pharmacology models integrate pharmacokinetics, pharmacodynamics, and systems biology to provide a comprehensive understanding of drug effects. By considering the intricate interplay between drugs, biological systems, and disease pathways, these models contribute to a holistic approach to drug development and personalized medicine.
Sources: en.wikipedia.org
Registered medical products are most often 0.1% nasal drops. Research suppliers ship lyophilized powder, usually in milligram quantities, which is dissolved before use. The active peptide is the same in both cases; presentation and excipients differ.
No. The peptide is synthetic, although it is modelled on a fragment of a naturally occurring hormone. ACTH(4-10) is generated when ACTH is cleaved, but the Pro-Gly-Pro extension is not a known endogenous sequence. It is therefore a designed analogue rather than a natural metabolite.
The label reflects reported effects on attention, memory and recovery after neurological injury in regional clinical reports. Those reports are mostly small and have not been widely replicated outside the region. The classification is descriptive and does not imply a single defined mechanism.
Semax is based on the ACTH(4-10) fragment, a seven-amino-acid segment of adrenocorticotropic hormone. The synthetic peptide retains the core sequence while removing regions associated with endocrine activity. This modification is intended to isolate effects on the nervous system.