This is a working overview of phosphocreatine, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2025-12-25. Anything still debated is marked as such rather than presented as settled.
In the human body, creatine is synthesized mainly in the liver and kidneys from the amino acids glycine, arginine, and methionine. Dietary sources include meat, fish, and other animal tissues, which supply preformed creatine. Because plant foods contain little or no creatine, dietary intake varies widely among populations. The compound is stored largely in skeletal muscle, where it is converted to phosphocreatine and used to regenerate adenosine triphosphate during short bursts of activity.
Creatine monohydrate is one of several solid forms of creatine described in the literature. Other forms include anhydrous creatine, creatine hydrochloride, and creatine ethyl ester, each with different solubility and stability characteristics. The monohydrate is distinct from creatinine, a spontaneous breakdown compound that forms when creatine loses water and cyclizes. Commercial descriptions sometimes use synonyms such as methylguanidoacetic acid or N-(aminoiminomethyl)-N-methylglycine, which refer to the same base molecule. These names appear in chemical databases and product labels.
Creatine monohydrate is stable under dry, cool conditions but can degrade when exposed to moisture and heat. In solution, it undergoes hydrolysis to creatinine, a cyclic derivative with little role in phosphagen energy transfer. The rate of conversion increases with temperature, storage time, and acidic or alkaline pH. Solid material kept in a sealed container at room temperature generally retains its composition for extended periods. Moisture uptake is a primary concern because it can accelerate breakdown and caking.
Analytical laboratories commonly use high-performance liquid chromatography to separate creatine from creatinine and related impurities. Ion chromatography, nuclear magnetic resonance, and titration assays can also quantify the compound. Water content is measured by Karl Fischer titration or loss on drying, because the monohydrate has a defined theoretical water fraction. Particle size, bulk density, and flowability are physical properties that affect blending and capsule filling. These measurements support quality control and help verify that a lot matches its specification.
Regulatory status varies by country. In the United States, creatine monohydrate is sold as a dietary supplement ingredient, while in the European Union it is placed on the market as a food supplement component. Some jurisdictions have established purity monographs or permitted health claims, while others treat it as a novel food or require notification. Product labels may state the amount of creatine monohydrate or the equivalent creatine content, and the two figures can differ. Independent testing programs sometimes check identity, potency, and contaminant limits.
| Property | Value | Notes |
|---|---|---|
| Chemical formula | C4H9N3O2·H2O | Monohydrate; anhydrous base is C4H9N3O2 |
| Molar mass | 149.15 g/mol | Calculated for the monohydrate form |
| Appearance | White crystalline powder | Typical laboratory and food-grade material |
| Solubility in water | Sparingly soluble at room temperature | Solubility increases with temperature |
| Common synonyms | Methylguanidoacetic acid; N-(aminoiminomethyl)-N-methylglycine | Synonyms refer to the creatine base, not the hydrate specifically |
Creatine monohydrate is a hydrated form of creatine, a nitrogen-containing compound involved in cellular energy metabolism. Its molecular formula is C4H9N3O2·H2O, with a molar mass around 149.15 g/mol. The monohydrate is the most common solid form used in research and commercial settings because it crystallizes readily and remains stable under ordinary conditions. The term monohydrate indicates one water molecule per creatine molecule in the crystal lattice. It appears as a white crystalline powder with low odor.
In the body, creatine is synthesized from arginine, glycine, and methionine, mainly in the liver and kidneys, and is also obtained from foods such as meat and fish. About 95% of body creatine is stored in skeletal muscle, where a fraction is phosphorylated to phosphocreatine. Phosphocreatine serves as a rapid reserve of high-energy phosphate for short bursts of ATP regeneration. The monohydrate form supplies creatine after dissolution and absorption, but it is not itself the active phosphorylated species.
Creatine was first identified in skeletal muscle extracts in the nineteenth century, and its role in phosphagen energy buffering was clarified in the twentieth century. The monohydrate salt became widely studied after methods for inexpensive synthesis and crystallization were developed. Modern research examines its effects on muscle energetics, recovery, and cognitive performance under specific conditions. Findings vary with population, exercise protocol, baseline creatine status, and measurement method. Studies often compare supplementation with placebo during controlled training or testing schedules.
Creatine monohydrate is a crystalline compound formed from creatine and one molecule of water. Its systematic name is N-(aminoiminomethyl)-N-methylglycine monohydrate, and it appears as a white, odorless powder with limited solubility in water. The monohydrate is the most common solid form used in research and commercial products because it is stable under dry conditions. The anhydrous form lacks the water of crystallization and differs slightly in molar mass. Both forms participate in the same biochemical reactions once dissolved.
In the body, creatine is synthesized from the amino acids arginine, glycine, and methionine, primarily in the liver and kidneys. It is transported to muscle and other tissues, where it is phosphorylated to phosphocreatine by creatine kinase. This phosphagen system provides a rapid source of adenosine triphosphate during short, intense contractions. Dietary creatine comes mainly from meat and fish, and the body's total pool is influenced by both synthesis and intake.
The enzyme characterised from Saccharopolyspora erythraea converts erythromycin D into erythromycin C by introduction of a hydroxy group at the C-12 position of the macrocycle. It uses reduced nicotinamide adenine dinucleotide phosphate (NADPH) and oxygen as cofactors. Erythromycin C is subsequently converted to the antibiotic, erythromycin A, by the enzyme erythromycin 3''-O-methyltransferase.
Wawrik, B; Paul, JH; Tabita, FR (2002). "Real-time PCR quantification of rbcL (ribulose-1,5-bisphosphate carboxylase/oxygenase) mRNA in diatoms and pelagophytes". Appl. Environ. Microbiol. 68 (8): 3771–3779. Bibcode:2002ApEnM..68.3771W. doi:10.1128/aem.68.8.3771-3779.2002. PMC 123995. PMID 12147471. Logan J; Edwards K; Saunders N, eds. (2009). Real-Time PCR: Current Technology and Applications. Caister Academic Press. ISBN 978-1-904455-39-4.
Computational neurogenetic modeling is concerned with the development of dynamic neuronal models for modeling brain functions with respect to genes and dynamic interactions between genes, on the cellular level (Computational Neurogenetic Modeling (CNGM) can also be used to model neural systems).
Sources: en.wikipedia.org
==== General paleoanthropology ==== Cerrito, Burkart & van Schaik (2026) review the techniques used to extract information on life history from hominin fossils. Towle (2026) reviews longstanding issues in the systematics of hominins, including non-monophyly of at least the genus Australopithecus and mosaic trait distribution among hominin taxa, and proposes to subsume the genera Paranthropus and Australopithecus within the genus Homo. Begun (2026) reviews the fossil record of African apes and humans, and argues that the lack of hominin fossils from Africa from the interval between 13.5 and 6–7 million years ago might not simply be the result of incompleteness of the fossil record, and is potentially consistent with the origin of hominins in Eurasia and their dispersal into Africa after 7 million years ago. Gardner et al. (2026) study changes of body size throughout the evolutionary history of hominins, and interpret their finding as consistent with marked body mass increase in members of the genus Homo other than Homo habilis and Homo rudolfensis. A study on the morphological diversity of the femur and the humerus in extant hominids is published by Aramendi (2026), who interprets her findings as indicative of variable utility of different long bones for taxonomic indentification of hominin fossils, and as indicating that some of the variability observed in isolated or fragmentary hominin fossils might not be caused by presence of more than one taxon in the studied fossil material.
Ajahn Brahm agrees, writing that the main purpose of dependent origination is to explain "how there can be rebirth without a soul" and "why there is suffering, and where suffering comes to an end." Brahm cites the definitions of the nidanas in the Vibhaṅgasutta (SN 12.2) which clearly indicate that birth and death is meant literally. According to Brahm,Paṭicca-samuppāda shows the empty process, empty of a soul that is, which flows within a life and overflows into another life. It also shows the forces at work in the process, which drive it this way and that, even exercising sway in a subsequent life. Dependent origination also reveals the answer to how kamma done in a previous life can affect a person in this life. Brahm argues that there are two parallel processes at work in dependent origination (which are really one process looked at from different angles), one is delusion and kamma leading to rebirth consciousness (nidanas # 1 – 3) and the other is craving and clinging leading to existence and rebirth (# 8 – 11). Brahm describes this as follows: "deluded kamma and craving produce the fuel which generates existence and rebirth (into that existence), thereby giving rise to the start of the stream of consciousness that is at the heart of the new life." Furthermore, dependent origination explains rebirth without appeal to an unchanging self or soul (atman). Paul Williams sees dependent origination as closely connected with the doctrine of not-self (anatman) which rejects the idea there is an unchanging essence that moves across lives.
Clonidine may be used to ease drug withdrawal symptoms associated with abruptly stopping the long-term use of opioids, alcohol, benzodiazepines, and nicotine. It can alleviate opioid withdrawal symptoms by reducing the sympathetic nervous system response such as tachycardia and hypertension, hyperhidrosis (excessive sweating), hot and cold flashes, and akathisia. It may also be helpful in aiding smokers to quit. The sedation effect can also be useful. Clonidine may also reduce severity of neonatal abstinence syndrome in infants born to mothers that are using certain drugs, particularly opioids. In infants with neonatal withdrawal syndrome, clonidine may improve the neonatal intensive care unit Network Neurobehavioral Score. Clonidine has also been suggested as a treatment for rare instances of dexmedetomidine withdrawal.
Sources: en.wikipedia.org
Creatine monohydrate is the hydrated solid form of creatine, a nitrogen-containing compound involved in cellular energy metabolism. It consists of one creatine molecule associated with one water molecule in a crystal lattice.
No. Creatinine is a breakdown product formed when creatine loses water and cyclizes, and it is not the same compound. The two names are similar but refer to different chemical structures and roles.
The body synthesizes creatine from amino acids, mainly in the liver and kidneys. It also comes from animal foods such as meat and fish, while plant foods contain little or none.
A sealed container at room temperature, away from moisture and direct heat, is suitable for most solid material. Keeping the lid closed limits water uptake and caking. Long-term storage in a refrigerator is not necessary if the powder remains dry.