Chemical Component Summary

Identifiers(2S)-2,5-bis(azanyl)pentanoic acid
FormulaC5 H12 N2 O2
Molecular Weight132.16

Chemical Details

Formal Charge0
Atom Count21
Chiral Atom Count1
Chiral AtomsCA
Bond Count20
Aromatic Bond Count0
Leaving AtomsOXT, H2, HE2, HXT

Drug Info: DrugBank

DrugBank IDDB00129 Different stereochemistry
  • approved
  • nutraceutical
DescriptionOrnithine is an amino acid produced in the urea cycle by the splitting off of urea from arginine. It is a central part of the urea cycle, which allows for the disposal of excess nitrogen. L-Ornithine is a precursor of citrulline and arginine.
  • (S)-2,5-Diaminopentanoate
  • (S)-2,5-Diaminopentanoic acid
  • (S)-2,5-diaminovaleric acid
  • (S)-alpha,delta-Diaminovaleric acid
  • (S)-ornithine
SaltsL-ornithine dihydrochloride
Brand Names
  • Primene 10%
  • Primene 10%-liq IV
Affected OrganismHumans and other mammals
IndicationUsed for nutritional supplementation, also for treating dietary shortage or imbalance. It has been claimed that ornithine improves athletic performance, has anabolic effects, has wound-healing effects, and is immuno-enhancing.
PharmacologyA non-essential and nonprotein amino acid, ornithine is critical for the production of the body's proteins, enzymes and muscle tissue. Ornithine plays a central role in the urea cycle and is important for the disposal of excess nitrogen (ammonia). Ornithine is the starting point for the synthesis of many polyamines such as putrescine and spermine. Ornithine supplements are claimed to enhance the release of growth hormone and to burn excess body fat. Ornithine is necessary for proper immune function and good liver function.
Mechanism of actionL-Ornithine is metabolised to L-arginine. L-arginine stimulates the pituitary release of growth hormone. Burns or other injuries affect the state of L-arginine in tissues throughout the body. As De novo synthesis of L-arginine during these conditions is usually not sufficient for normal immune function, nor for normal protein synthesis, L-ornithine may have immunomodulatory and wound-healing activities under these conditions (by virtue of its metabolism to L-arginine).
Route of administrationIntravenous
  • Dietary Supplements
  • Supplements
CAS number70-26-8
Drug Info/Drug Targets: DrugBank 3.0: a comprehensive resource for 'omics' research on drugs. Knox C, Law V, Jewison T, Liu P, Ly S, Frolkis A, Pon A, Banco K, Mak C, Neveu V, Djoumbou Y, Eisner R, Guo AC, Wishart DS. Nucleic Acids Res. 2011 Jan; 39 (Database issue):D1035-41. | PMID:21059682