Abstract

1. Tannic acid is definitely toxic for mice and rats when given by intravenous or subcutaneous injection.

2. When applied to deep subcutaneous tissues following surgical removal of the skin, tannic acid was lethal for mice, but not for rats or rabbits. Tannic acid, or possibly its degradation products, could be detected in the urine of all the foregoing animals by chemical tests.

3. Liver damage was produced in rabbits when tannic acid was administered by subcutaneous injection, but not when the drug was applied to denuded surfaces. The production of liver damage therefore appears to depend on the quantity of tannic acid absorbed.

4. When injected intraperitoneally, tannic acid depresses the water diuresis of rats markedly. This depression could not be produced by the subcutaneous injection of large doses, or by applying the drug to denuded surfaces.