Portal de Periódicos da CAPES

Toxicity of the genus Dieffenbachia

1969; Elsevier BV; Volume: 15; Issue: 1 Linguagem: Inglês

10.1016/0041-008x(69)90129-x

1096-0333

Frederick W. Fochtman, Joseph E. Manno, Charles L. Winek, Jeanne A. Cooper,

Pharmacogenetics and Drug Metabolism

A series of tests was undertaken to evaluate the toxicity of Dieffenbachia and also to elucidate the toxic constituent(s). The juice of two species of Dieffenbachia were used, D. picta and D. exotica. The reaction of the albino Wistar rat to the instillation of the juice from the plant into the oral cavity was very similar to the reaction observed in the human upon accidental ingestion. Single-dose oral toxicity determination in rats showed an LD50 > 160 ml/kg. An eye irritation study in albino rabbits showed principally conjunctival involvement and some reversible damage to the cornea. An oxalic acid determination on the whole plant and on the juice of D. exotica gave values of 0.37% and 0.15%, respectively; for D. picta, 0.21% and 0.10%. Blood histamine concentrations were determined on rats treated with the juice of D. picta, and the levels were significantly increased over those of untreated animals. Histologic examination of tongue tissue from animals treated with Dieffenbachia juice showed edema, vascular congestion, degeneration of the basement membrane, and an inflammatory reaction. Trypsin digestion of the juice decreased the toxicity observed in the rat mouth. Rats pretreated with diphenhydramine hydrochloride, histologically showed some protection to the effects of the juice, but treatment with cortisone acetate only delayed the reaction. The toxicity of the juice is attributed to a labile "proteinlike" substance, not to the oxalate content as previously believed. The mechanism of toxicity seems to be associated with histamine release.