Clinical Toxicology Lecture 1 General management of Poisoning

CLINICAL TOXICOLOGY
Lecture 1
1. General principles involved in the management of poisoning
Prof. (Dr.) Daniel Xavier Prasad
Sree Krishna College of Pharmacy and Research centre ,Parassala , Trivandrum ,Kerala .+91 9042884053,+919488218753 dxprasad@gmail.com
YouTube cannel:- Pick Pharma DXP@dxprasad
Toxicology is that aspect of Pharmacology that deals with the adverse effects of drugs.
It is concerned not only with drugs used in therapy but also with the many other chemicals that may be responsible for household, environmental, or industrial interaction.
The word toxicology is derived from toxicon – a poisonous substance into which arrow heads were dipped and toxikos – a bow.
The study of poisons must have started by 1500 B.C. because the Ebers Papyrus, the earliest collection of medical records, contains many references and recipes for poisons.
Paracelsus summarized this concept in the following famous phrase: “All substance are poisons: there is none that is not a poison .
The right dose differentiates a poison from a remedy.”
This concept is especially crucial to the safe use of drugs but also important for the safe handling of other chemicals.
Types of toxic substance:-
Drugs: - Drugs have usually been designed to be highly potent in biological systems and consequently many are potentially toxic.
Drug toxicity may be due either to an overdose or it may be a rare and unusual adverse effects.
2. Food Additives: - food additives are usually of low biological activity.
Many different additives are now added to food to alter the flavor or color, prevent spoilage, or in some other way change the nature of the foodstuff.
There are also many potentially toxic substances which may be regarded as contaminants occurring naturally in food, resulting from cooking, or from other contamination
3. Industrial Chemicals: - Industrial chemicals may contribute to environmental pollution, and they may be a direct hazard in the workplace where they are used, formulated or manufactured.
4. Environmental pollutants: - the main sources of pollution are industrial processes and the deliberate release into the environment of substance such as pesticides.
5.Natural Toxins: - Many plants and animals produce toxic substance for both defensive and offensive purposes.
Natural toxins of animal, plant and bacterial origin comprise a wide variety of chemical types, cause a variety of toxic effects and are a significant cause of human poisonings.

The most visible pollutants, but perhaps not the most significant, are smoke from power stations and factories.
Factories may also produce and emit more potent substance in smaller quantities although the level of these in generally controlled.
Environmental pollutants may be released into the air, river or sea water or dumped onto land.
6.Household Poisons: - These may include some of the substance in the other categories such as pesticides, drugs and solvents.
Exposure to these types of compounds is usually acute rather than chronic.
Many of the household substances used for cleaning are irritants and some are corrosive.
Poisoning refers to the development of dose-related adverse effects following exposure to chemicals, drugs, or other xenobiotics.
To paraphrase Paracelsus, the dose makes the poison.
In excessive amounts, substances that are usually innocuous, such as oxygen and water, can cause poisoning.
Conversely, in small doses, substances commonly regarded as poisons, such as arsenic and cyanide, can be consumed without ill effect.
Hormesis is a biological response where low doses of a substance are beneficial, while high doses are harmful.
Xenobiotic :- Foreign chemical; do not generally contribute to body growth or enter pathways for eventual production of energy
Potency:- Relationship between incidence or intensity of an effect & dose required to produce effect used as a standard for comparison of different chemicals
What are harmful or adverse effects? Harmful or adverse effects are those that are damaging to either the survival or normal function of the individual.
What is Toxicity? The word "toxicity" describes the degree to which a substance is poisonous or can cause injury. The toxicity depends on a variety of factors: dose, duration and route of exposure, shape and structure of the chemical itself, and individual human factors
What is Toxic? This term relates to poisonous or deadly effects on the body by inhalation (breathing), ingestion (eating), or absorption, or by direct contact with a chemical
What is a Toxin? The term "toxin" usually is used when talking about toxic substances produced naturally. A toxin is any poisonous substance of microbial (bacteria or other tiny plants or animals), vegetable, or synthetic chemical origin that reacts with specific cellular components to kill cells, alter growth or development, or kill the organism.
What is a Toxicant? A toxicant is any chemical that can injure or kill humans, animals, or plants; a poison.