In vitro study of the effectiveness of three commercial adsorbents for binding oleander toxins

Introduction: Oleander (Nerium oleander) poisoning is a common problem found in many parts of the world. The oleander toxicity is due to oleandrin and its aglycone metabolite oleandrigenin. Activated charcoal is a useful gastrointestinal decontamination agent that limits the absorption of ingested toxins. A relatively new clay product, Bio-Sponge^TM, containing di-tri-octahedral smectite as the active ingredient, is also recommended for adsorbing bacterial toxins in the gastrointestinal tract. Bio-Sponge ^TM has been used to prevent gastrointestinal absorption of oleander toxins in livestock but the efficacy of activated charcoal and Bio-Sponge ^TM for adsorbing oleandrin and oleandrigenin has not yet been studied. Methods: An in vitro experiment to compare the efficacy of three commercially available adsorbents was performed. The adsorbents include Bio-Sponge^TM, ToxiBan^TM granules, and a generic grade activated charcoal. Results: ToxiBan^TM granules have the highest adsorptive capacity, followed by the generic grade activated charcoal, and finally, Bio-Sponge^TM. Discussion: Bio-Sponge^TM did not adsorb oleandrin and oleandrigenin at concentrations that are expected to be present in the gastrointestinal tract of poisoned animals. Conclusions: On the basis of this in vitro study, products containing activated charcoal are more effective for binding oleander toxins and providing gastrointestinal decontamination than products containing di-tri-octahedral smectite. However, the ability of these adsorbents to alter the clinical outcome in oleander-poisoned animals or humans is yet to be evaluated.