TOXICOLOGY

CHAPTER ELEVEN

Learning objectives:

After completing this chapter the student will be able to:

1. describe commonly encountered poisons
2. understand the measures employed for the management of poisoning

INTRODUCTION

Toxicology is concerned with the deleterious effects of chemical and physical agents on all living systems. The terms poison, toxic substance and toxicant are synonymous. The most important axiom of toxicology is that “the dose makes the poison”, indicating that any chemical or drug can be toxic if the dose or exposure becomes high enough. Poisoning occurs by non-therapeutic substances such as household and environmental agents, and due to over-dosage of therapeutic substances. Poison may be ingested accidentally or deliberately. A difficult challenge to the health care provider is the identification of the toxicant and limited availability of antidotes. Thus, the health care provider in most cases, may be limited with symptomatic therapy.

“Treat the patient, not the poison” remains the most basic and important principle of clinical toxicology.

A toxic response can occur within minutes or after a delay of hours, days, months or years. Acute toxicities are of particular interest for practicing health care provider.

General measures in poisoning

The treatment of a poisoned patient requires a rapid and genuine approach. There are three principles underlying the management of poisoning:

• Life support
• Drug identification
• Drug detoxification