Everything below concerns nasal drops. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2025-12-27. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
Purity assessment relies mainly on reversed-phase high-performance liquid chromatography, which separates the target heptapeptide from truncated sequences, deletion analogues, and oxidised forms. Mass spectrometry, usually coupled to liquid chromatography, confirms identity through the expected molecular ion and reveals modifications such as methionine sulfoxide formation. Amino acid analysis can verify composition, and tandem mass spectrometry supports sequence confirmation. Ultraviolet detection near 254 to 280 nanometres is convenient because the phenylalanine and histidine residues absorb in that region. Nuclear magnetic resonance is rarely used for routine release testing.
Common degradation pathways include oxidation of the methionine side chain, hydrolysis of the peptide backbone, and aggregation under unfavourable pH or concentration. Stability studies typically monitor the main peak by chromatography and report total related substances as a percentage. Because no official monograph exists, acceptance criteria vary between laboratories, and reported purity values are not directly comparable across suppliers. Analysts therefore document the method, column, and detection wavelength alongside each result, and open questions remain about how much biological activity the oxidised forms retain.
Solid semax is typically supplied as a lyophilised powder that is hygroscopic and sensitive to moisture, light, and repeated temperature cycling. Long-term storage of the dry peptide is generally recommended at approximately -20 degrees Celsius, while shorter working periods may use refrigeration at 2 to 8 degrees Celsius. Vials should remain tightly closed and desiccated when brought to room temperature, because condensation can damage the material before it is weighed. Dividing a batch into aliquots is preferable to thawing one container repeatedly.
| 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 |
Clinical reports describe use in ischaemic stroke, transient ischaemic attack, optic nerve conditions, and cognitive complaints, but most of these studies are small and were conducted in a single region. Systematic reviews have generally described the evidence base as limited in size and variable in methodological quality. Randomised controlled data suitable for international regulatory assessment are scarce. As a result, major treatment guidelines outside Russia do not include the peptide, and interest in it remains largely research-driven rather than routine clinical.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It is described in the literature as an analogue of the ACTH(4–10) fragment, a short N-terminal portion of adrenocorticotropic hormone that retains some neurotropic activity without the full hormonal effects of the parent peptide. The molecule carries a methionine residue at the N-terminus and two proline residues near the C-terminus, features that shape both its interactions with receptor systems and its chemical stability. The free peptide corresponds to the formula C37H51N9O10S and a molecular mass near 813.9 Da.
Lyophilised powder is normally kept at -20 °C in a desiccated container, with some suppliers recommending -80 °C for long-term archival storage. Repeated freeze-thaw cycles are the most common cause of avoidable loss, so aliquoting before freezing reduces variability between working sessions. Dissolved peptide is far less stable than the dry solid and is usually prepared fresh or held briefly at 4 °C. Aqueous solutions support both hydrolysis of the backbone and oxidation of the N-terminal methionine, and these two routes dominate degradation under ordinary laboratory conditions.
Identity and purity are confirmed with reversed-phase high-performance liquid chromatography, typically monitored at 214 nanometres where the peptide bond absorbs. Mass spectrometry, either electrospray or MALDI-TOF, verifies molecular mass against the theoretical value and detects truncation or adduct formation. Amino acid analysis and peptide mapping provide additional confirmation when required. The most frequently reported impurities are deletion sequences from incomplete coupling, methionine sulfoxide from oxidation, and dimeric species formed through non-covalent aggregation. Impurity profiles depend strongly on the synthesis and purification route chosen by the producer.
The compound was developed during the 1980s at the Institute of Molecular Genetics in Moscow as part of research on fragments of adrenocorticotropic hormone. Early work examined short ACTH-derived sequences that retained neurotrophic effects while lacking the endocrine activity of the full hormone. Semax entered clinical use in Russia during the 1990s, where it received registration for several neurological indications. Outside that region it remained primarily a laboratory research material rather than an approved therapeutic. English-language literature on it grew more slowly and frequently cited the original Russian studies.
Terminology around the compound varies by source. It appears in catalogues and papers as Semax, as the heptapeptide ACTH(4-7)-Pro-Gly-Pro, and under various alphanumeric laboratory codes used by individual suppliers. These names refer to the same sequence but may imply different salt forms, purity grades, or counter-ions. Peptide databases usually list the free base mass, while product descriptions sometimes report acetate or trifluoroacetate salts with a different formula weight. Because naming conventions for research peptides are not standardised across vendors, checking the declared sequence and measured mass is more reliable than relying on a trade name alone.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its design combines the ACTH(4-7) core fragment with a C-terminal Pro-Gly-Pro extension, a modification intended to improve stability and prolong activity. The molecule is hydrophilic, carries no lipid chains or glycosylation, and has a theoretical mass just over 810 daltons in its free form. All seven residues are proteinogenic amino acids, so no non-natural building blocks appear in the backbone. A free N-terminal methionine and C-terminal proline define the unmodified parent peptide.
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=== Medications === Caffeine sometimes increases the effectiveness of some medications, such as those for headaches. Caffeine was determined to increase the potency of some over-the-counter analgesic medications by 40%. The pharmacological effects of adenosine may be blunted in individuals taking large quantities of methylxanthines like caffeine. Some other examples of methylxanthines include the medications theophylline and aminophylline, which are prescribed to relieve symptoms of asthma or COPD.
Long-term use of benzodiazepines is associated with increased risk of cognitive impairment and dementia, and a reduction in prescribing levels is likely to reduce dementia risk. The association of a history of benzodiazepine use and cognitive decline is unclear, with some studies reporting a lower risk of cognitive decline in former users, some finding no association and some indicating an increased risk of cognitive decline. Benzodiazepines are sometimes prescribed to treat behavioral symptoms of dementia. However, like antidepressants, they have little evidence of effectiveness, although antipsychotics have shown some benefit. Cognitive impairing effects of benzodiazepines that occur frequently in the elderly can also worsen dementia.
== January 19, 1982 (Tuesday) == The explosion of a boiler at the Star Elementary School in Spencer, Oklahoma, killed five children and a schoolteacher while they were at lunch in the school cafeteria, and injured 35 others. The Iran Liberation Front was founded by former Prime Minister Ali Amini and other Iranians in exile in Paris with the goal of restoring the Iranian monarchy (abolished in 1979) and placing former Crown Prince Reza Pahlavi, son of Mohammad Reza Pahlavi, last Shah of Iran, as head of state. Funded by the American CIA, the Front would achieve its greatest success on September 5, 1986, by overriding all Iranian television channels to deliver an 11-minute speech from Reza Pahlavi. The Coca-Cola Company announced its plans to purchase ownership of the filmmaker Columbia Pictures. Born: Juan García Postigo, Spanish actor and model known for winning the 2007 Mister World male beauty competition; in Málaga Died: Semyon Tsvigun, 64, Soviet Ukrainian intelligence agent, deputy to Soviet KGB Director (and future Soviet Communist Party leader Yuri Andropov), died from an apparent suicide. Leopold Trepper, 77, Polish-born Soviet anti-Fascist espionage leader of the Red Orchestra spy network, later imprisoned in the Soviet Union after being accused of cooperation with Germany as a prisoner of war, died in Israel, where he had been allowed to emigrate in 1973. Marya Zaturenska, 80, Russian-born American lyric poet and 1938 Pulitzer Prize winner.
Spider angiomata or spider nevi happen when there is dilatation of vasculature beneath the skin surface. There is a central, red spot with reddish extensions that radiate outward. This creates a visual effect that resembles a spider. It occurs in about one-third of cases. The likely cause is an increase in estrogen. Cirrhosis causes a rise in estrogen due to increased conversion of androgens into estrogen. Palmar erythema, a reddening of the palm below the thumb and little finger, is seen in about 23% of cirrhosis cases, and results from increased circulating estrogen levels. Gynecomastia, or the increase of breast size in men, is caused by increased estradiol (a potent type of estrogen). This can occur in up to two-thirds of cases. Hypogonadism signifies a decreased functionality of the gonads. This can result in impotence, infertility, loss of sexual drive, and testicular atrophy. A swollen scrotum may also be evident. Liver size can be enlarged, normal, or shrunken in people with cirrhosis. As the disease progresses, the liver will typically shrink due to the result of scarring. Jaundice is the yellowing of the skin. It can additionally cause yellowing of mucous membranes notably of the white of the eyes. This phenomenon is due to increased levels of bilirubin, which may also cause the urine to be dark-colored.
Sources: en.wikipedia.org
Acetaminophen (or paracetamol) is an analgesic medication that can affect the liver when administered in high doses. Acetaminophen is predominantly conjugated into glucuronate and sulfate moieties by Phase II metabolism. A small percentage is metabolized by the cytochrome P450 pathway to a toxic metabolite, NAPQI. NAPQI is conjugated by glutathione to non-toxic cysteine and mercapturic acid moieties. In cases of acetaminophen toxicity, the Phase II conjugation enzymes are saturated, and a higher fraction is converted to NAPQI. The conjugation of NAPQI to glutathione occurs until glutathione is depleted from hepatic reserves, after which the toxic NAPQI accumulates and causes damage to the hepatocytes. This occurs primarily in areas of the liver that are relatively poorly perfused with oxygen, or furthest away from the hepatic artery, termed Zone 3. Acetaminophen overdose is associated with Zone 3 necrosis, to the point that acute liver failure may result. The King's College Criteria identify two groups of patients that have a poor prognosis with acetaminophen induced liver failure:
Many drugs as tablets, capsules, or drops are taken orally. Administration methods directly into the stomach include those by gastric feeding tube or gastrostomy. Substances may also be placed into the small intestines, as with a duodenal feeding tube and enteral nutrition. Enteric coated tablets are designed to dissolve in the intestine, not the stomach, because the drug present in the tablet may either cause irritation in the stomach or else be degraded by stomach acids/enzymes.
Malonylation occurs mainly in mitochondria but also in the cytosol and nucleus. In mouse liver, about 60% of malonylated proteins are mitochondrial, whereas in human fibroblasts the distribution is more even. Succinylation and glutarylation are likewise enriched in mitochondria but not exclusive to them. The relative abundance of these modifications reflects acyl-CoA availability: acetylation is most common, succinylation reaches 10–30 % of acetylation levels, malonylation is at least tenfold less frequent, and glutarylation occurs only in trace amounts. In addition to their differing frequencies, malonylation, succinylation, and acetylation can also target the same lysine site. In mouse liver mitochondria, about 85 % of succinylation sites overlap with at least one of these modifications, and ~6 % can contain all three, mainly in proteins involved in fatty acid oxidation, glutaryl-CoA degradation, and ketogenesis. In contrast, only 55 % of malonylation sites overlap with succinylation, while about 45 % are unique. These distinct patterns suggest a specific regulatory role for malonylation among lysine acyl modifications.
*Iron = ~3 g in males, ~2.3 g in females Of the 94 naturally occurring chemical elements, 76 are listed in the table above. Of the remaining 18, it is not known how many occur in the human body. Most of the elements needed for life are relatively common in the Earth's crust. Aluminium, the third most common element in the Earth's crust (after oxygen and silicon), serves no function in living cells, but is toxic in large amounts, depending on its physical and chemical forms and magnitude, duration, frequency of exposure, and how it was absorbed by the human body. Transferrins can bind aluminium.
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.
Dry powder is usually kept at about -20 degrees Celsius for long-term storage and at 2 to 8 degrees Celsius for short working periods. Containers should stay sealed and protected from light and moisture to limit degradation.