This is a working overview of nasal drops, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2025-09-29. Anything still debated is marked as such rather than presented as settled.
Semax is a synthetic heptapeptide developed in the Soviet Union during the 1980s by researchers at the Institute of Molecular Genetics in Moscow. It was designed as a truncated analog of adrenocorticotropic hormone, retaining only the fragment spanning residues four through ten. Investigators sought a peptide that would preserve the cognitive effects associated with ACTH while eliminating the hormonal stimulation of the adrenal cortex. The compound entered clinical use in Russia during the following decade.
Russian regulatory authorities approved the peptide for nasal administration, and it remains listed in the national pharmacopoeia under several trade names. Documented indications include acute ischemic stroke, transient ischemic attacks, traumatic brain injury, and certain ophthalmological and neurological conditions. Physicians also prescribe it for cognitive complaints in older patients, although the evidence base for that use is thinner. Outside Russia and a few neighboring states, the substance is not an approved medicine and is sold instead as a research chemical.
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It corresponds to the ACTH(4-7) fragment extended at the C-terminus by a Pro-Gly-Pro tripeptide, an addition intended to slow enzymatic breakdown. The molecular formula is C37H51N9O10S and the molecular mass is approximately 814 daltons. In the literature it is often described as an ACTH(4-10) analog, although that label reflects a naming convention as much as a precise structural relationship. The compound was developed in Russia and remains most closely associated with that research tradition.
Laboratory descriptions of the material are consistent across suppliers. It appears as a white to off-white lyophilized powder that dissolves readily in water and in polar organic solvents such as dimethyl sulfoxide. Aqueous solutions are clear and colorless at low concentrations. Because the peptide contains methionine, oxidation at the sulfur atom is a recognized degradation pathway, and handling notes usually call for protected, desiccated storage. Reported purity for research-grade lots is generally above 95 percent as measured by reversed-phase high-performance liquid chromatography.
The compound is registered in Russia as a pharmaceutical product, most commonly formulated as a nasal solution, and has been used in that setting since the 1990s. Outside that jurisdiction it is generally handled as a research chemical rather than an approved medicine. Regulatory status therefore differs sharply between countries, and material sold internationally may not correspond to the Russian pharmaceutical formulation. Documentation with commercial samples is typically limited to a certificate of analysis covering purity and identity, not clinical status or local legal classification.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic heptapeptide | Analog of an ACTH fragment |
| Amino acid length | Seven residues | Met-Glu-His-Phe-Pro-Gly-Pro |
| Origin | Moscow, 1980s | Institute of Molecular Genetics |
| Approved regions | Russia and some neighboring states | Not cleared in Western markets |
| Common trade names | Multiple national brands | Sold as a nasal formulation |
Semax is a synthetic peptide created in the Soviet Union during the early 1980s by researchers working in Moscow. It was built from the short adrenocorticotropic hormone fragment known as ACTH(4-10), and the chain was then extended with three additional amino acids. The resulting molecule was named semax and entered clinical use in Russia in 1994. It is generally described as a nootropic and neuroprotective agent rather than as a hormone analogue.
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.
== Structure and bonding == Esters derived from carboxylic acids and alcohols contain a carbonyl group C=O, which is a divalent group at C atom, which gives rise to 120° C–C–O and O–C–O angles. Unlike amides, carboxylic acid esters are structurally flexible functional groups because rotation about the C–O–C bonds has a low barrier. Their flexibility and low polarity is manifested in their physical properties; they tend to be less rigid (lower melting point) and more volatile (lower boiling point) than the corresponding amides. The pKa of the alpha-hydrogens on esters of carboxylic acids is around 25 (alpha-hydrogen is a hydrogen bound to the carbon adjacent to the carbonyl group (C=O) of carboxylate esters). Many carboxylic acid esters have the potential for conformational isomerism, but they tend to adopt an S-cis (or Z) conformation rather than the S-trans (or E) alternative, due to a combination of hyperconjugation and dipole minimization effects. The preference for the Z conformation is influenced by the nature of the substituents and solvent, if present. Lactones with small rings are restricted to the s-trans (i.e. E) conformation due to their cyclic structure.
Due to its sedative and tranquilizing properties, it was used to quiet the minds of those with psychosis, help with people who were considered insane, and also to help treat patients with insomnia. However, despite its medicinal values in these cases, it was noted that in cases of psychosis, it could cause anger or depression, and due to the drug's euphoric effects, it could cause depressed patients to become more depressed after the effects wore off because they would get used to being high. The standard medical use of opium persisted well into the 19th century. US president William Henry Harrison was treated with opium in 1841, and in the American Civil War, the Union Army used 175,000 lb (80,000 kg) of opium tincture and powder and about 500,000 opium pills. During this time of popularity, users called opium "God's Own Medicine". One reason for the increase in opiate consumption in the United States during the 19th century was the prescribing and dispensing of legal opiates by physicians and pharmacists to women with "female complaints" (mostly to relieve menstrual pain and hysteria). Because opiates were viewed as more humane than punishment or restraint, they were often used to treat the mentally ill. Between 150,000 and 200,000 opiate addicts lived in the United States in the late 19th century and between two-thirds and three-quarters of these addicts were women. Opium addiction in the later 19th century received a hereditary definition. Dr.
(death announced on this date) 14 October – Rosalind Howells, Baroness Howells of St Davids, 94, British politician, member of the House of Lords (1999–2019). 20 October – Oliver Colvile, 66, British politician, MP (2010–2017). 25 October – Dick Taverne, 97, British politician, MP (1962–1974) and member of the House of Lords (1996–2025). 3 November – John Marshall, 85, British politician, MEP (1979–1989) and MP (1987–1997). 11 November – Helen Newlove, Baroness Newlove, 63, British community reform activist, member of the House of Lords (since 2010). 16 November – Mark Fisher, 81, British politician, minister for the arts (1997–1998) and MP (1983–2010). 17 November – David Pryce-Jones, 89, British conservative commentator, author and historian. 27 November – Peter Whittle, 64, British politician, member of the London Assembly (2016–2021), cancer. 28 November – Sir John Stanley, 83, British politician, MP (1974–2015). 8 December – Kate Allsop, 71, British politician, mayor of Mansfield (2015–2019). (death announced on this date) 17 December – Sir Patrick McNair-Wilson, 96, English politician, MP (1964–1966, 1968–1997). (death announced on this date) 30 December – Joe Byrne, 72, Northern Ireland politician, MLA (1998–2003, 2011–2015). 31 December – Mary Bradley, 83, Northern Irish politician, MLA (2003–2011). (death announced on this date)
Sources: en.wikipedia.org
The definition of the topical route of administration sometimes states that both the application location and the pharmacodynamic effect thereof is local. In other cases, topical is defined as applied to a localized area of the body or to the surface of a body part regardless of the location of the effect. By this definition, topical administration also includes transdermal application, where the substance is administered onto the skin but is absorbed into the body to attain systemic distribution. If defined strictly as having local effect, the topical route of administration can also include enteral administration of medications that are poorly absorbable by the gastrointestinal tract. One such medication is the antibiotic vancomycin, which cannot be absorbed in the gastrointestinal tract and is used orally only as a treatment for Clostridioides difficile colitis.
Lysine malonylation (Kmal, maK), protein malonylation or malonylation, is a reversible post-translational modification (PTM) in eukaryotic and prokaryotic cells, in which a malonyl group (–CO–CH2–COOH) is added to a lysine (K) residue of a protein. It was first identified in 2011 by Peng et al. as an evolutionarily conserved modification and belongs to the acidic acyl modifications such as succinylation and glutarylation. As a dynamically regulated modification, it responds to conditions such as stress responses, metabolic processes, and mutations, thereby influencing the charge, structure, and function of proteins. This involves, among other things, the metabolic pathways of glucose and fatty acids as well as histone-mediated gene regulation, and is increasingly associated with immune regulation, angiogenesis, osteoarthritis, cancer and metabolic diseases such as obesity and type 2 diabetes. Its biological significance is increasingly recognized, but many aspects of its regulation and function remain unresolved, so that its therapeutic potential is still unexplored.
Gillnets may be used in fish maw fishing. However, gillnets can have high rates of bycatch. In the Gulf of California, gillnets set by poachers to catch totoaba also inadvertently catch vaquita, a critically endangered porpoise. The population of vaquita dropped 92% from 1997 to 2015, in large part from totoaba poaching. The 2019 documentary Sea of Shadows documented and condemned totoaba poaching and its negative effect on the vaquita population. In the Kikori River Delta of Papua New Guinea, gillnet fishermen trying to target the scaly croaker Nibea squamosa regularly trap elasmobranchs and dolphins as bycatch: targeted fish make up less than a quarter of the total catch.
Sources: en.wikipedia.org
It originated at the Institute of Molecular Genetics in Moscow during the 1980s. The work was carried out by a Russian research group that specialized in peptide neuropharmacology.
It is registered as a medicine in Russia and has been used clinically there for decades. No regulatory agency in Western Europe or North America has approved it for any indication.
Semax corresponds to the four-to-ten fragment of adrenocorticotropic hormone. Because it omits the first three residues, it lacks the adrenal-stimulating action of the full hormone.
It is registered as a pharmaceutical product in Russia, where it is typically supplied as a nasal solution. In most other countries it is not an approved drug and is traded as a research chemical instead. Approval status depends entirely on the jurisdiction involved.