Veterinary Taxicology

INTRODUCTION

• Toxicokinetics differs from pharmacokinetics. In clinical toxicology cases one deals with:
• Potential poisoning (not yet absorbed)
• Actual toxicoses (altered physiology may alter kinetics over time)
• Residue contamination of foods such as meat, milk, or eggs
• Whether the problem relates to poisoning or residues, toxicokinetic data may be used either:
  • to predict 'normal' rates of metabolic change (activation or detoxification) and/or elimination, or
  • to choose methods to help decrease the toxicant concentration at the receptor (e.g., to limit absorption, or increase detoxification or excretion)
• As compared to typical uses of therapeutic drugs, in toxicoses, kinetics are more likely to be altered by:
• Saturation of enzymes involved in metabolism (detoxification or toxification) or of enzymes employed in carrier systems necessary for elimination
• Organ system dysfunction or failure : For toxicant-induced liver or kidney damage that alters metabolism and/or elimination of the toxicant e.g. circulatory problems resulting in hypotension secondary to shock, acidosis due to exertion and seizures.
• Before toxicity can develop, a substance must come into contact with a body surface such as skin, eye or mucosa of the alimentary or respiratory tract.