Drug-excipient compatibility testing-Identification and characterization of degradation products of phenylephrine in several pharmaceutical formulations against the common cold

J Pharm Biomed Anal. 2011 Jul 15;55(5):949-56. doi: 10.1016/j.jpba.2011.03.027. Epub 2011 Mar 25.


Different pharmaceutical preparations against the common cold containing phenylephrine (PHE) and saccharose were studied. New impurities were discovered in these preparations after exposure using isocratic ion-pair chromatography separation on a C18 column. LC-MS and NMR techniques were employed to identify and to fully characterize these new compounds. The products were identified as 1-[5-(hydroxymethyl)-2-furyl]-2-methyl-1,2,3,4-tetrahydroisochinolin-4,8-diol and 1-[5-(hydroxymethyl)-2-furyl]-2-methyl-1,2,3,4-tetrahydroisochinolin-4,6-diol. Identification of these degradation products allowed to understand and to confirm their formation mechanism. The developed HPLC method separates of all known impurities and impurities originated from PHE as well.

MeSH terms

  • Chemistry Techniques, Analytical
  • Chemistry, Pharmaceutical / methods*
  • Chromatography, High Pressure Liquid / methods
  • Chromatography, Liquid / methods
  • Drug Contamination
  • Drug Stability
  • Excipients / chemistry*
  • Magnetic Resonance Spectroscopy / methods
  • Mass Spectrometry / methods
  • Models, Chemical
  • Pharmaceutical Preparations / analysis
  • Phenylephrine / analysis*
  • Phenylephrine / chemistry
  • Sucrose / analysis


  • Excipients
  • Pharmaceutical Preparations
  • Phenylephrine
  • Sucrose