| Phenelzine ((beta)-phenylethyl hydrazine) is a drug which is used to treat mental depression. It is the only antidepressant which is effective according to the DESI review. It is a "status drug" among psychiatrists, however, no systematic studies of phenelzine degradation have been published in the past fifty years.;The Arrhenius plots show that the activation energies in various buffers as a function of pH are similar.;Increasing the concentration of phenelzine does not increase the rate of phenelzine degradation proportionately. When oxygen is purged through the buffered phenelzine solution the degradation rate increases only at higher pH's.;This study shows that 0.1% EDTA can stabilize phenelzine solution.;This study shows that an apparent first order rate of phenelzine degradation is obtained by measuring the disappearance rate of phenelzine. The pH-log rate profile shows that under anaerobic conditions, the decomposition in an acidic solution is an important reaction. However, under aerobic conditions, the rate of phenelzine degradation is higher in neutral and basic solutions. The primary salt effect and acid-base catalysis can occur in phenelzine solutions.;The degraded solution of phenelzine in neutral pH solution has been analyzed by GC, HPLC, and GC-MS. The following degradation products have been found: benzene, toluene, ethylbenzene, styrene, phenylethylamine, phenylacetic acid, phenylethanol, benzaldehyde, phenylacetaldehyde, phenethyl methyl ether, and pheneylethyl methyl ketone.;Degradation mechanisms for phenelzine have been suggested. The kinetic model and proposed rate law of phenelzine has been described. |
