TOXICITY STUDIES ON AMBERLITE XE-96, A CARBOXYLIC TYPE CATION EXCHANGE RESIN

¹ Research Division, Smith, Kline & French Laboratories, Philadelphia, Penna.

1. Subacute and chronic toxicity studies in dogs and rats on feeding the purified ammonium salt of a carboxylic exchange resin, Amberlite XE-96 (SKF No. 648), in doses of 3-5 gm./kgm. daily from one week to six months, gave no evidence of changes due to administration of this cation exchanger.

2. Three successive generations of rats were fed SKF No. 648 at a level of 10 per cent of their food intake for periods of 500, 300, and 225 days, respectively. This uninterrupted administration of a carboxylic cation exchange resin did not produce any untoward effects in the animals of each generation, as evidenced by growth studies, hematological examination, reproduction record, tissue electrolyte content, endocrine gland weights, and histopathological examination of the principal organ systems, and is evidence, therefore, that this resin does not interfere with the absorption and utilization of vitamins, amino acids, and other essential nutrients.

3. Administration of a mixture of potassium and ammonium salts of this carboxylic resin, in the form of Resodec, to dogs for 170 days at a daily dose of 30 gm. produced no deleterious response.

4. The data obtained in these experiments provide sufficient evidence of safety, on both short and long-term administration, to justify the clinical evaluation of this resin preparation as an agent for producing sodium restriction in edema due to salt retention.