What is poisoning and how to react to it [Archives:2004/741/Health]
By Dr. Bhoopendra Singh*
Etymologically speaking Toxicology is derived from toxicon (arrow of poison) + logos (knowledge). Toxicology, therefore, has been defined as the study of the adverse effects of chemicals on living organisms.
Until a few decades ago, toxicology was considered to be no more than a branch of forensic science and criminology. Nowadays, it is clear that the study of applied toxicology in its various forms- Clinical toxicology, Occupational toxicology, Forensic, Environmental toxicology etc. and related areas are important, if not vital, to the continued development of life on earth.
Clinical toxicology is the branch of toxicology dealing with the prevention, diagnosis and management of poisoning.
Analytical toxicology is the branch of toxicology that provides support for the diagnosis, prognosis and management of poisoning.
What is poison?
A substance is a poison if it causes deleterious effects on human body when that is exposed to it. In practice, however, only those substances that are associated with a great risk of harmful effects are designated as poisons. No substance is a poison by itself; it is the dose that makes a substance a poison. All the drugs are poison and all poisons are drugs. It means that the presence of a potentially poisonous substance in an organism does not mean that poisoning has taken place; most of us have certain quantities of lead, mercury, arsenic, DDT, BHC in our bodies, but it cannot be said that we are poisoned by these substances. As a rule, a substance is a poison only in toxic doses, for which our body systems are not able to detoxify. Virtually, any substance, even pure salt, and water, can be poisonous when taken in toxic doses.
Toxicology is the starting point of many drugs, whether they are of botanical origin or synthetically prepared. In this connection, consider the poisonous Foxglove (Digitalis purpurea), the therapeutic agent used to treat a cardiac patient, the acetyl cholinesterase inhibitors of the organophosphorus type that were originally developed for chemical warfare, later used as insecticide, and now used to treat glaucoma.
In essence, there is no difference between the action or mechanism of action of a drug and that of a poison. The difference between a drug and a poison is relative. Effects of a drug should be seen as unwanted if they do not help alleviate the ailment for which the drug is used. One can state that all actions of a drug given to a healthy individual and not used for proper indication are toxic actions; in such a case, the drug has the character of a poison. For example, the Mydriatic action of atropine in the hands of an ophthalmologist is the therapeutic action, while inhibition of secretion is an unwanted side effect and that is a poisonous action.
Poisoning: Any substance or micro-organism which when administered or exposed in small quantity produces deleterious effects (disease) on the body.
What is disease? Disease, as a broad term, includes all sorts of abnormalities even some that we do not usually refer to as a disease, such as cuts and bruises. It can be defined as any deviation from or interruption of the normal structure or function of any part, organ, or system (or combination thereof) of the body that is manifested by a characteristic set of symptoms and signs and whose etiology, pathology and prognosis may be known or unknown.
Etiology or causes of diseases: The concept that certain abnormal symptoms or diseases are “caused” is as ancient as recorded history. For the Arcadians (2500 BC), if someone got ill, it was the patient's own fault or the makings of outside agents, such as bad smell, cold, evil spirits, or gods. In modern terms, there are two major classes of etiologic factors- intrinsic or genetic and acquired (examples- infectious, nutritional, chemicals and physicals).
Types of poisoning
Poisoning can be acute or chronic.
Acute poisoning refers to situations where the effects are directly related to the ingestion of the substance as a single or multiple exposures occurring within a short time (less than 24 hours).
Chronic poisoning refers to the situations where there is often an ingestion of a small quantity of the substance over a long period of time leading to toxic concentrations and thus to symptoms of poisoning.
The acute exposure of lead in a large dose causes colic abdominal pain whereas a small dose of the same over a long period of time leads to neurotoxicity i.e. loss of memory and IQ.
Handling poisoning emergencies
Proper management of poisoning requires expert guidance. The most important single resource in handling poisoning emergencies is the local/regional poison control/ information center. You can approach the emergency/ casualty in the hospital to get assistance in case of acute poisoning. Your local centers are listed in the telephone book white/yellow pages or may be obtained from Directory Assistance. Affix this number to all telephones or post it in a conspicuous place, such as a bulletin board next to a telephone. All family members as well as baby-sitters should know when and how to call this number. When calling the poison control center:
– Be prepared to give as much information as possible. The person answering the phone will want to know your name, location, and telephone number, so he can call back in case you are disconnected, or can summon help, if needed.
– Give the name of the substance ingested and, if possible, the amount and time of ingestion. If the bottle or package is available, give the trade name and ingredients if they are listed.
– Describe the state of the poisoning victim. Is the victim conscious? Are there any symptoms? What is the person's general appearance, skin color, respiration, breathing difficulties, mental status (alert, sleepy, unusual behavior)? Vomiting? Convulsions? Using this information, the poison center specialist can give specific first-aid instructions. The majority of the cases called into poison control centers can be handled at home if instructions are followed promptly and correctly. All households, especially those with children, should have on-hand syrup of ipecac to induce vomiting (which is recommended in only certain cases of poisoning). Activated charcoal, when taken by mouth, prevents the intestinal absorption of a large number of ingested substances and is often given by health professionals to treat poisoning. (Currently it is recommended for use only by medical personnel.) There is no such thing as a universal antidote.
First aid for poisoning
Always call your local poison control center/emergncy hospital for advice
– Remain calm and don't panic. You need to act quickly. If Victims are unconscious, they need immediate emergency care.
– Keep the airway open and perform artificial respiration until emergency care arrives.
– If you are unable to reach a poison control center or a local hospital emergency department for advice, transport the victim to the nearest emergency service.
– If you are far from medical assistance (greater than 30 minutes), the following general guidelines should be applied in the absence of specific instructions from a poison control center or other reliable source:
1. Determine the nature of the ingested substance. If there are no visible bottles or other clues, examine the mouth for signs of burns, which would indicate an acid or alkali. Smell the breath for a petroleum-like odor.
2. Diluting the poison by administering water or milk is advised for most substances. Water is recommended for acid and alkali ingestion if the person can swallow.
For poisoning by swalloing:
1. Check the victim's airway, breathing, and circulation. If necessary, begin rescue breathing and CPR (DEFINE: Cardiopulmonary Resuscitation (CPR) consists of mouth-to-mouth respiration and chest compression)
2. Try to make sure that the victim has indeed been poisoned. It is not always obvious. Some signs include chemical-smelling breath, burns around the mouth, difficulty breathing, vomiting, or unusual odors on the victim. If possible, identify the poison.
Follow instructions given by the poison control/emergency center. You may be told to take the victim to an emergency room and/or to induce vomiting. (This will depend on the poison taken).
If necessary, vomiting can be induced by:
– Giving Syrup of Ipecac and at least one glass of water. Dosage for Syrup of Ipecac: 1 Tbsp. (5 ml) for children 1-3 years old; 1-2 Tbsp. (10 ml) for persons 3-6 years and 2-4 Tbsp (10-20 ml) in adults followed by 2 glasses of water (This is available over-the-counter at drug stores). If the victim does not vomited in 25 minutes, repeat the dose of the Syrup. Another technique is to use a glass of warm water containing 3 teaspoons of salt (Note that don't administer more amount of salt solution) or 1 spoonful of dried mustard powder.
– Tickling the back of the throat with a finger, spoon handle, pen, or other blunt object after giving water can be useful but with proper precautions.
Do not induce vomiting if: i) The nature of the substance is unknown. ii) A corrosive substance (house cleaner, lye, bleach, or other acid or alkali product) is suspected. iii) A petroleum product (benzene, kerosene, gasoline, turpentine, paint thinner, other hydrocarbon) is suspected. Vomiting a petroleum product carries the danger of inhaling it into the lungs, causing chemical pneumonia. iv) Milk or milk of magnesia is usually suggested to be given to neutralize them. v) The person is having seizures, is unconscious or appears to be losing consciousness. vi) The victim is less than 1 year of age. Take the poisoning victim, along with the bottle or container of whatever was ingested, and any vomitus to the nearest hospital emergency department for further treatment.
3. If the victim vomits, protect the airway and must clear the victim's airway, wrap a cloth around your fingers before cleaning out his or her mouth and throat.
4. If the patient/victim needs to be taken to an emergency room, bring the poison's container with the label intact. If possible, collect the vomitus so it can be examined/analyzed.
5. Monitor the victim's vital signs (temperature, pulse, rate of breathing, blood pressure). If the victim starts having convulsions, protect him or her from injury and give first aid.
6. Reassure the victim and keep him or her comfortable while getting or awaiting medical help. If the poison has spilled on the victim's clothes, remove the clothing and flush the skin with water.
For inhalation poisoning:
1. Call for emergency help. Never attempt to rescue without notifying others first.
2. Rescue the victim from the danger of the gas, fumes, or smoke. Hold a wet cloth over your nose and mouth. Open windows and doors to remove the fumes.
3. Avoid lighting a match as some gases may ignite.
4. Take several deep breaths of fresh air, then hold your breath as you go in.
5. After rescuing the victim from danger, check his or her airway, breathing, and circulation. If necessary, perform rescue breathing and CPR.
6. As necessary, perform first aid for skin burns, eye injuries (eye emergencies), or convulsions (convulsion, first aid).
7. If the victim vomits, protect his or her airway.
8. Even if the victim seems perfectly fine, get medical help.
Prevention:
u Be aware of poisonous substances in and around your home. Take steps to protect young children from these.
u Be familiar with plants in your home, yard, and vicinity. Keep your children informed too. Remove any noxious plants.
u If you think that industrial poison might be polluting nearby land or water, report your concerns to the local health department or the state or Environmental Protection Agency.
u Most non-food substances are poisonous if ingested in large doses.
u Teach children about the dangers of substances that contain poison. Label all poisons.
u Keep all your prescription and non-prescription drugs stored out of the reach of children.
u Don't store household chemicals in food containers, even if they are labeled.
* Visiting Professor,
Department of Forensic Medicine & Toxicology,
Faculty of Medicine, Sana'a University, Sana'a
Department of Forensic Medicine & Toxicology
Casturba Medical College,
Manipal Academy of Higher Education,
Manipal, Karnataka, India.
Email: [email protected] & [email protected]
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