Intro Toxico.pptx..............................

GENERAL
TOXICOLOGY
Dr. VISHAL B.SURWADE,
MBBS, MD, MBA(HA)
Professor

Swiss Physician Paracelsus (1493-1541 AD)
“All substances are poisons: there is none
which is not a poison.
The right dose differentiates a poison from
a remedy.”

Toxicology
The science that deals with the knowledge of
source , character & property , Symptoms
produced , Nature & Fatal effect,
Lethal dose & Remedial procedure used to
combat the action of poison.
In another words: EVERYTHING ABOUT POISONS.
It also concerned with law relating to their sale &
prescription.

Toxinology
Toxinology is the specialized area of
toxicology that deals specifically with
biological toxins, such as venoms or
poisonous plants.

Any substance, administered in whatever way,
produces ill effects, diseases or death.
• May be Synthetic / Mineral / Animal or Vegetable origin.
• Can be given by – Oral (Mouth) , Inhalation (Nose),
Parenteral (Injection)- S/C,IM,IV or through Skin contact.
• Drug :
It is any substance or mixture of substances destined for
administered for use in the Diagnosis , Treatment,
Investigation , Prevention of Disease or Modification of
physiological functions.

In law the real difference between a
medicine and a poison is the INTENT with
which it is given .
Sec 284 of IPC lays down the punishment for
careless handling of poisons.
Sec. 299,304A,324,326,328 of IPC deals with
offences relating to administration of such
substances.

An apparently nontoxic chemical can be toxic at
high doses. (Too much of a good thing can be
bad).
Highly toxic chemicals can be life saving when
given in appropriate doses. (Poisons are not harmful
at a sufficiently low dose)
More than 50,000 people die every year from toxic
exposure in India.
More than 1 million illness world wide by some
poison, this may be tip of iceberg.

Sources of Poisons
1. Domestic or household sources - In domestic
environment poisoning may more commonly occur
from detergents, disinfectants, cleaning agents,
cosmetics, antiseptics, insecticides, Rodenticides etc.
2. Agricultural and horticultural sources- different
insecticides, pesticides, fungicides and weed killers.
3. Industrial sources- In factories, where poisons are
manufactured or poisons are produced as by
products.

Sources of Poisons
4. Commercial sources- From store-houses, distribution
centers and selling shops.
5. From uses as drugs and medicines – Due to wrong
medication, overmedication and abuse of drugs.
6. Food and drink – contamination in way of use of
preservatives of food grains or other food material, additives
like colouring and odour agents or other ways of accidental
contamination of food and drink.
7. Miscellaneous sources- snake bite poisoning, air pollution,
sewer gas poisoning etc.

Laws on poisons
1. The Drugs and Cosmetics Act,1940
2. The Drugs and Cosmetic Rules, 1945:Classified drugs into
schedules
1. Schedule C: biological/special products
2. Schedule E: list of poisons
3. Schedule F: vaccines & sera
4. Schedule G: hormone preparations
5. Schedule H: drugs to be sold on prescription
6. Schedule J : diseases for cure of which no drug should be advertised
7. Schedule L: antibiotics, anti- histaminics and other recent
chemotherapeutic agents

Laws on poisons
3. The Pharmacy Act,1948: regulation of profession
of pharmacy.
4. The Drugs Control Act,1950: control of sale,
supply and distribution of drugs
5. The Drugs & Magic Remedies (objectionable
Advertisement) act,1954

The Narcotic Drugs and Psychotropic
Substances – NDPS Act (1985)
NDPS act impose complete prohibition of cultivation of
coca, poppy, Cannabis Indica plants, manufacture,
purchase , sale of narcotic substance.
Minimum punishment is 10-20 years rigorous
imprisonment and fine of Rs. 1-2 lakh.

Poisoning in India
Human Poisoning
Cattle poisoning

HUMAN POISONING
Suicidal
Homicidal
Stupefying agent
Accidental
All are more common in India because
Easily availability & careless in storage.

 CATTLE POISONS
Either accidental or due to action of enemy
desiring to take revenge.
They are used by leather factory or owner to
destroy cattle when they are useless.
Poisons used to destroy cattle are----
Abrus precatorius, arsenic, yellow oleander,
Nux vomica, snake venom.

Classification depending on presentation of Symptoms
1. Fulminant :
Produced by a massive dose. Death occurs rapidly
sometimes without preceding symptoms.
2. Acute :
Produced by a single dose or several small doses
taken in a short period. Symptom abrupt.
3. Chronic :
Produced by small doses taken over a long period.
Onset is insidious.
4. Subacute :
Characterized by a mixture of features of Acute &
Chronic poisoning.

1.Corrosives
Highly active irritant.
Produces inflammation & ulceration of tissues.
Strong acid & strong alkalies.
Includes:-
Mineral acids- Sulfuric acid, Nitric acid, HCl.
Organic acid- Oxalic acid, Acetic acid, Salicylic acid

2. Irritants
They produced symptoms of pain in abdomen,
vomiting, purging.
Post mortem evidences are seen by naked eyes ,
i.e. redness and ulceration of gut.
Corrosives in dilute form act as irritants.

3.Neurotics
Acts chiefly on nervous system , some have local
irritant action.
Cerebral + Spinal + Peripheral Nervous system
Act after absorption.
Chief symptoms: Headache, drowsiness, giddiness,
delirium, coma, convulsion, paralysis etc.

Poisons have specific action on-
1) Cerebrum
2) Spine
3) Peripheral

1) Cerebral have four effects:-
Somniferous (Reduces pain + induce sleep)
includes opium and alkaloids.
Inebriants includes alcohol, anesthetic agent ,
sedatives & hypnotics , Hydrocarbon fuels.
Stimulants includes anti-depressants,
Amphetamines & Caffeine
Deliriant includes Dhatura, belladona ,
cannabis, cocaine.

2) Spinal- acts on spinal cord
includes Nux vomica & its alkaloids
3)Peripheral –acts on PNS include
curare & conium.

4.CARDIAC
Acting on heart.
Digitalis, oleander ,aconite , tobacco.

5.ASPHYXIANTS
Acts on lungs & include
Irrespirable gases like carbon monoxide,
Carbon dioxide, sewer gases and war gases.

6.MISCELLANEOUS
Poisons having widely different action
Food poisoning.
Agriculture Pesticides
Habit forming drugs
( Substances of abuse)

ROUTE OF ADMINISTRATION
1.Enteral route- through mouth (Most common)
2.Parenteral route- Injections
3.Inhalation- through air passage
4.Topical-External surface application
5.Introduction into natural orifices.
6.Sublingual route.

Actions of Poisons
Local- at the site of application
Remote- away from site, but limited to one or two organs
Systemic- involving multiple organs
General – over all

DUTIES OF MEDICAL PRACTITIONER IN A
CASE OF POISONING
The duties of medical practitioner are both
1) Legal
&
2) Professional

MEDICOLEGAL DUTIES OF DOCTOR
(TEN COMMANDMENTS)
1.If the case of poisoning is accidental or suicidal in nature, the attending
Doctor is under no legal obligation to notify the police,
but Death must be informed to Police.
2.Doctors working in Government Hospitals are required to report every case
of Poisoning to Police
3.All cases of homicidal poisoning must be reported to Police per Section 39
of Cr.P.C. Failure to do so will make him culpable under Sec.176 of IPC

Contd…..
4.If Police require information on any case of Poisoning, the attending
Doctor has to divulge it. No scope for professional secrecy. If not,
Doctor will be held culpable under Sec.202 & 193 of IPC
5.Every efforts must be made by attending Doctor to collect & preserve
evidence suggestive of poisoning.
Deliberate omission to do so, can attract punishment under Sec.201 IPC.
6.Collect vomitus, fecal matter, stomach washings,
stained clothes, contaminated food &
dispatch it to the nearest FSL.

Contd….
7.Record the dying declaration relating to the circumstances. Call
Magistrate but if not possible, Doctor himself must record the
declaration as per Sec.32,Clause 1 of IEA
8.If the patient dies before the exact diagnosis could be made out, or the
patient is brought Dead, the Doctor must notify the police, who will
order Autopsy.

Contd…..
9.Detailed written record should be made with respect to every case
of poisoning & kept in safe custody.
10.If Doctor comes across a case of Food poisoning from a public
eatery. He must notify the public health authority.

In order to summarize the duties…..
The duties of the RMP in a case of suspected poisoning-
(TRIPP)
Duty to Treat
Duty to Record
Duty to Inform
Duty to Post Mortem
Duty to Preserve

GENERAL LINE OF TREATMENT
A. Stabilise the Patient
B. Removal of unabsorbed poison material from
the system (Decontamination)
C. Antidotes
D. Elimination of absorbed poison by Excretion
E. Symptomatic treatment

A. Stabilise the Patient(Scandinavian Method)
Very important to stabilize the patient first of all
&
to treat the most imminent danger to life
immediately

 B. Removal of the poisoning material from
the system (Decontamination)
• In cases of inhaled poisons, the individual
should be shifted to fresh air and artificial
ventilation should be started.
• In cases of injected poisons from bite or an
injection, a ligature should be tied to prevent it
from further reaching the circulation.
The ligature is loosened for one minute after every ten
minutes to prevent gangrene formation.

In case of contact poisons affecting the skin,
mucous membrane, should be irrigated with
water and neutralized by application of suitable
Chemical antidotes.

In all ingested poisons the guidelines to treatment are:
1. The stomach should be emptied by gastric
lavage or emesis but emetics are avoided in
corrosive intake.
2. Appropriate antidote should be given to
neutralize the poisonous compound even
despite gastric lavage and emesis as some
poisons are secreted again in stomach after
having been absorbed.
3.Symptomatic treatment.

In ingested poisons, the methods of
decontamination are:
(i) Gastric lavage/ Stomach wash
(ii) Emesis
(iii)Administration of Antidotes

STOMACH WASH (GASTRIC LAVAGE)
Gastric lavage is indicated in patients who
present within 3 hours of ingestion of poison.
 The stomach wash can also be carried in the
presence of gastric secretions, delayed
gastric emptying or in case of ingestion of
sustained release medications.

 Gastric Lavage Tube:
 For gastric lavage, a soft rubber tube with a funnel at its
one end known as Ewald or Boa’s tube is most commonly
used.
 In adults an ordinary, soft, non-collapsible tube with 36-40
French size having one cm diameter and 1½ mts length is
used.
 Length is 150 cm

In children with 22-28 French size (Ryle’s tube) diameters
should be used.
The tube should have an attached funnel at one end and
the other end should be rounded with lateral openings.
There is a mark at a distance of 50 cm from its rounded end.
A suction bulb is placed at the mid of to tube to pump
out stomach contents.
Ryle’s tube is also called as Naso-Gastrc Tube
Length is 105 cm

Procedure for Stomach Wash
Before performing stomach wash, the patient
should be lying in a left lateral position or in a
prone position with head hanging over the edge
of the bed and the face is positioned downwards
The mouth is at a lower level than the larynx
and chances of aspiration of fluid are
eliminated.

The gastric lavage tube is gently passed in to
the stomach through the mouth by lubricating with
glycerin or Vaseline jelly up to a distance of 50 cm in
adults and 25 cm in children.
The position of the tube in stomach can be checked by
stethoscope
Initially 250- 300 mL of warm (35 Degree C.) saline or plain
water is passed through the funnel held high up.

The stomach contents can be siphoned
by the use of suction bulb, by lowering the
funnel portion.
The first sample of stomach wash should
be preserved for chemical analysis.
Then stomach wash is carried out with
chemical agents specific to the poisons.

In cases where Potassium Permanganate (a powerful
oxidizing agent) is used as gastric lavage fluid, the
gastric lavage is continued till the colour of lavage
fluid is colourless, odorless and no particulate matter is
visible.

Complications of Gastric Lavage
1. Laryngeal spasm.
2. Aspiration pneumonitis.
3. Perforation of stomach or esophagus.
4. Sinus bradycardia and ST elevation on ECG.

Contraindication of Gastric Lavage
The contraindication for stomach wash are
absolute and relative.
Absolute contraindication:
1. Corrosive poisoning except Carbolic & Oxalic acid
(Organic Corrosives) as there is danger of perforation.
2. Comatose patient as there is risk of aspiration
3. Volatile poisons due to the risk of inhalation.
4. If the patient is hypothermic.

Relative contraindication:
1. If the patient is suffering from alimentary tract
diseases like esophageal varices.
2. Comatose patients.
3. Ingestion of alkali.
4. Advanced pregnancy.
5. Any hemorrhagic diathesis.
6. Any history of recent surgical operation.

Contraindications can be summarised…
poisoning by Corrosives.
C (K)erosene and other volatile poisons
Convulsions in patients
Comatose patient
Constrictions in (diseases) of stomach and esophagus.
Hemorrhagic diathesis
Esophageal varices
Recent surgery
Advanced pregnancy

EMESIS
The easiest way to induce vomiting is by inducing
the gag reflex.
Also vomiting can be produced by the use of
emetics.
The emesis should be avoided as there is danger
of aspiration of stomach contents.

Complications of Emesis
1. Features of cardio toxicity such as Bradycardia,
Atrial fibrillation and Myocarditis.
2. Aspiration Pneumonitis.
3. Esophageal tears may be caused due to
protracted vomiting.

ADMINISTRATION OF ANTIDOTES
An antidote is defined as “agents which counteracts
or neutralize the effects of a poison.”
In various poisonings, the antidotes are used to
counteract the Patho-physiology produced by a
toxin.

Four types of Antidotes:
1. Mechanical or Physical
2. Chemical
3. Physiological
4. Chelating Agents
1. MECHANICAL OR PHYSICAL ANTIDOTES
The mechanical antidotes counteract the
effect of poison by mechanically preventing
their absorption without inactivating the
damaging action of the poisons.

Activated Charcoal
 Activated charcoal is a fine, black, odorless and tasteless type of
amorphous carbon.
 Finely powdered activated charcoal acts mechanically by ADSORBING &
retaining within its pores.
 Usual Dose: 1 gm/ Kg of the body (50-100 gm in adults & 10-30 gm in a
child)
 Why the word ACTIVATED?
 Made from burning wood, coconut shell, bone , sucrose or rice starch.
 Treated with an activating agent:
 Steam & CO2
 Resulting particles are small but have an extremely large surface area.

Disadvantages:
Constipation
Pulmonary aspiration
Intestinal obstruction
Contraindications:
Absent bowel sounds
Intestinal obstruction
Caustic ingestion
Ingestion of petroleum
products

Other examples of Mechanical antidotes
DEMULCENTS
Fat, oil & egg albumen, milk, starch, Aluminium
Hydroxide: It prevents the action of poisons by
forming a coating on the mucous membrane of
the stomach.
Bulky food: Mechanical antidote for glass dust
by catching it within its bulk. Eg: Banana

CHEMICAL ANTIDOTES
The agents which counteracts the action of poisons by
forming harmless or insoluble compounds when brought
into contact with them.
Only those substances should be selected as chemical
antidotes which are by themselves almost harmless, so that
if an excess is given they will not produce any ill-effects.
Examples:
Vinegar or lemon juice in caustic alkali
KMnO4: Oxidising agent
For gastric lavage

PHYSIOLOGICAL/ Pharmacological ANTIDOTES
It acts on the tissues and various systems of the body and
produce signs and symptoms opposite to the signs and
symptoms produced by the poison.
They antagonize the effects produced by the poisonous
substance.
They are basically of use when some of the poison has
already been absorbed in to the circulation.
Reduces the toxic conversion of poison: Ethanol in Methanol
Blocking the receptor: Atropine in OPP
Competition at receptor site: Naloxone in Opiate poisoning

CHELATING AGENTS (Greek, Chele= Crab)
 These agents interacts with the poison to form an inert
complex, which is then excreted from the body.
 Primarily used in case of heavy metal poisoning
 These agents with metal ions forms ring structure within their
molecule.
They are
1.B.A.L.
2.EDTA
3.Desferoxamine.
4.Penicillamine.

British Anti-lewisite (B.A.L) Dimer caprol
B.A.L. was originally used as an antidote for
Lewisite, a vesicant containing arsenic that was
used as war gas.
This compound is used in heavy metal poisoning
especially Arsenic, Mercury, Lead, Antimony.

UNIVERSAL ANTIDOTE
Universal antidote comprises of:
1. Activated powdered charcoal—2 parts by weight
2. Magnesium oxide—2 parts by weight
3. Tannic acid—1 part by weight
15 gms of this powdered mixture added to ½ glass of
warm water .
The use of universal antidote is
obsolete now-a-days but this can definitely used
as a first-aid measure at homes.

ELIMINATION OF POISON:EXCRETION
In case of the poison has already absorbed
In case of severe poisoning
High risk of morbidity & mortality
Deterioration
Poison is producing delayed but serious toxic
effects

Excretion can be done by
Large fluid: forced diuresis
Haemodialysis
Whole bowel irrigation (Whole Gastric Lavage) :
Instillation of large volume of fluids into GI tract
producing
Previously Saline was used. voluminous diarrhoea
Special solutions(Very safe to use): Polyethylene Glycol
& Electrolyte Sol. (PEG-ELS) & PEG-3350

DIAGNOSIS OF POISONING
A) in living-
 history
 symptoms and signs
 certain investigations etc.
B) in dead-
 history,
 post-mortem findings,
 chemical analysis of viscera etc.
 Various laboratory techniques which are used to qualitatively and
quantitatively analyse and estimate poisons in the body-
 Chromatography, spectrometry, mass spectrophotometry,
immunoassay etc.

POISONING IN DEAD
Evidence depends upon
1)Post mortem examination
2)Chemical analysis
3)Experiment on animals
4) Histopathological Preservation

Post mortem Examination
Careful examination of alimentary system.
Sign may be hyperemia , softening ,ulceration,
perforation.
Rule out any other pathology.
In case of doubt, do Histopathology examination.
Careful and meticulous autopsy.

External Examination
1. Stains or marks of vomit or fecal matter on clothing and body.
2.Evidence of corrosion around mouth.
3.Presence of jaundice----Hepato toxic poisons(Yellowish sclera).
4.Odour in the vicinity of mouth(Fetor Hepaticus).
5.Color of PM lividity- specific for some poisons
e.g. Carbon monoxide - Cherry pink
Cyanide - Brick red
Hydrogen Sulphide - Greenish blue

5.Injection marks – in drug addict
6.Putrefactive changes –some poisons
retard the rate of decomposition e.g.
arsenic.

 CHEMICAL ANALYSIS
Important in analytical detection of poisoning.
Mandatory to preserve viscera in each case of
suspected poisoning.

VISCERA PRESERVATION
Stomach with it’s contents Loop of small intestines
1/3 of Liver with gall bladder ,1/2 of each kidneys,
½ of spleen
Blood for chemical analysis
Preservative Solution: Saturated Salt sol.

CIRCUMSTANTIAL EVIDENCES
Detail history from friends and relatives.
Any history of recent purchase of poisons.
Environment of patient and conduct of family
members.
Any abnormal anxiety or nervousness in relation to
dispose of the body by relatives.

MEDICOLEGAL ASPECTS
 ACCIDENTAL POISONING:
Occupational exposure
Consumption of contaminated food stuff
 SUICIDAL POISONING:
Mostly impulsive deliberate self-poisoning in young people
• HOMICIDAL: Rare

Intro Toxico.pptx..............................

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