Substance P is an undecapeptide member of the tachykinin neuropeptide family mainly secreted by neurons and is involved in many biological processes, including nociception and inflammation. The endogenous receptor for substance P is neurokinin 1 receptor although it also activates neurokinin 2 and neurokinin 3. Substance P is involved in the axon reflex-mediated vasodilatation to local heating and wheal and flare reaction. It has been shown that vasodilatation to substance P is dependent on the NK1 receptor located on the endothelium. In contrast to other neuropeptides studied in human skin, substance P-induced vasodilatation has been found to decline during continuous infusion. Preclinical data support the notion that Substance P is an important element in pain perception. The sensory function of substance P is thought to be related to the transmission of pain information into the central nervous system. Substance P coexists with the excitatory neurotransmitter glutamate in primary afferents that respond to painful stimulation. Substance P and other sensory neuropeptides can be released from the peripheral terminals of sensory nerve fibers in the skin, muscle, and joints. It is proposed that this release is involved in neurogenic inflammation, which is a local inflammatory response to certain types of infection or injury. Substance P appears to have an important role in nausea and vomiting. In 2004, the NK1 antagonist aprepitant (brand name Emend) was approved by the U.S. FDA for the treatment of chemotherapy-induced nausea and vomiting

Vidarabine or 9-β-D-arabinofuranosyladenine (ara-A, trade name Vira-A) is a synthetic purine nucleoside analog with in vitro and in vivo inhibitory activity against herpes simplex virus types 1 (HSV-1), 2 (HSV-2), and varicella-zoster virus (VZV). The inhibitory activity of Vidarabine is highly selective due to its affinity for the enzyme thymidine kinase (TK) encoded by HSV and VZV. This viral enzyme converts Vidarabine into Vidarabine monophosphate, a nucleotide analog. The monophosphate is further converted into diphosphate by cellular guanylate kinase and into triphosphate by a number of cellular enzymes. in vitro, Vidarabine triphosphate stops replication of herpes viral DNA. When used as a substrate for viral DNA polymerase, Vidarabine triphosphate competitively inhibits dATP leading to the formation of 'faulty' DNA. This is where Vidarabine triphosphate is incorporated into the DNA strand replacing many of the adenosine bases. This results in the prevention of DNA synthesis, as phosphodiester bridges can longer to be built, destabilizing the strand.

The ammonium cation is a positively charged polyatomic ion with the chemical formula NH4+. Ammonium ions are a waste product of the metabolism of animals. In fish and aquatic invertebrates, it is excreted directly into the water. In mammals, sharks, and amphibians, it is converted in the urea cycle to urea, because urea is less toxic and can be stored more efficiently. In birds, reptiles, and terrestrial snails, metabolic ammonium is converted into uric acid, which is solid and can therefore be excreted with minimal water loss. Ammonium is an important source of nitrogen for many plant species, especially those growing on hypoxic soils. However, it is also toxic to most crop species and is rarely applied as a sole nitrogen source. The ammonium ion (NH4+) in the body plays an important role in the maintenance of acid-base balance. The kidney uses ammonium (NH4+) in place of sodium (Na+) to combine with fixed anions in maintaining acid-base balance, especially as a homeostatic compensatory mechanism in metabolic acidosis. When a loss of hydrogen ions (H+) occurs and serum chloride (Cl–) decreases, sodium is made available for combination with bicarbonate (HCO3–). This creates an excess of sodium bicarbonate (NaHCO3) which leads to a rise in blood pH and a state of metabolic alkalosis. The therapeutic effects of Ammonium (as Ammonium Chloride) depend upon the ability of the kidney to utilize ammonia in the excretion of an excess of fixed anions and the conversion of ammonia to urea by the liver, thereby liberating hydrogen (H+) and chloride (Cl–) ions into the extracellular fluid.

Magnesium diamide is used as a chemical intermediate. Magnesium diamide is spontaneously combustible. It is toxic by inhalation. Skin or eye contact may cause severe burns.

Calcium lactate is the salt that consists of two lactate anions for each calcium cation (Ca2+); this salt is used as a calcium supplement to treat hypocalcemia. However, as a source of free calcium, this salt is less convenient than calcium citrate. Calcium lactate inhalation powder also called as PUR118 participated in phase I clinical trials to determine whether this formulation was safe and tolerable in a population of subjects with Cystic Fibrosis (CF). PUR118 also was used in another clinical trials to evaluate its effect on ozone-induced airway Inflammation in healthy normal volunteers in case of Chronic Obstructive Pulmonary Disease (COPD). The obtained results revealed that PUR118 reduced the severity of acute exacerbations in COPD and CF and had the beneficial impacts on mortality, morbidity, and quality of life in affected individuals. However, both studies were discontinued.

L-threonine is an essential amino acid. Threonine is a precursor of glycine. The biochemical studies on rats proved that glycine is synthesized from threonine (through threonine dehydrogenase pathway). Threonine dehydrogenase is the key enzyme in mammals like pigs, cat, and rats for degradation of 80% threonine. In adult humans, degradation of 7–11% of threonine is done by threonine dehydrogenase. The human L-threonine 3-dehydrogenase gene (GeneID: 157739, UniProtKB: Q8IZJ6 (TDH_HUMAN)) is an expressed pseudogene having lost the splice acceptor site preceding exon 6 and codon arginine-214 (CGA) is mutated to a stop codon (TGA). A few trials demonstrated that oral L-threonine may alleviate clinical signs of amyotrophic lateral sclerosis and spasticity in humans. L-Threonine has recently been brought into agricultural industry for balancing the livestock feed.

Leucine is an α-amino acid used in the biosynthesis of proteins. Leucine is an essential hydrophobic amino acid. It is used in the Leucine may be used some people as a supplement to build muscle. Leucine is also found in fish, meat, and poultry. In the pharmaceutical industry, L-leucine is used for parenteral and enteral nutrition and feeding, and is also used as a flavoring product and tablet lubricant in manufacturing. Leucine is an mTOR activator. It is a dietary amino acid with the capacity to directly stimulate muscle protein synthesis. As a dietary supplement, leucine has been found to slow the degradation of muscle tissue by increasing the synthesis of muscle proteins in aged rats. Long-term leucine supplementation does not increase muscle mass or strength in healthy elderly men. Leucine potently activates the mammalian target of rapamycin kinase that regulates cell growth. Infusion of leucine into the rat brain has been shown to decrease food intake and body weight via activation of the mTOR pathway.