GLYCERITE OF HYDROGEN PEROXIDE WITH UREA: III. Comparison by In Vitro Methods of Its Bacteriotoxic Action with That of Three Proprietary Aural Preparations

FOLLOWING the first reports¹ of the efficacy of glycerite of hydrogen peroxide in treatment of infections of the middle ear, subsequent studies showed the solution to be bacteriotoxic for Mycobacterium tuberculosis hominis² and for all oral fusiform and spirochetal organisms³ in both in vivo and in vitro tests. For this paper, the solution was compared with three proprietary aural preparations. The laboratory methods used simulated as closely as possible the clinical conditions for which such solutions are prescribed.

The solutions of glycerite of hydrogen peroxide, which were also compared with each other, had the following formulas:

1. Hydrogen peroxide, 1.46 per cent, as derived from urea peroxide, 4 per cent, with oxine (8-hydroxyquinoline, 8-quinolinol), 0.1 per cent, in glycerin.

2. Hydrogen peroxide, 1.5 per cent, as derived from hydrogen peroxide, 92 per cent, with or without oxine, 0.1 per cent, in glycerin.

The control solutions consisted of glycerin, glycerin with oxine, 0.1 per