general principles of poisoning and their treatment in pharmacology

1. P.S.V COLLEGE OF
PHARMACEUTICAL SCIENCE AND
RESEARCH

2. PHARMACOLGY-Ill
Subject staff:M.RAMASAMY,M.pharm
(Pharmacology).
Presentation by:T.ABISHEK.,B.Pharm,
(III-year)

3. TOPIC:GENERAL PRINCIPLES OF
TREATMENT OF POISONING

4. CONTENTS:
1.Introduction
2.Sources
3.Signs and symptoms
4.Diagnosis
5.Treatment

5. INTRODUCTION
Toxicology:
It is the science that deals with study of
poisons,their source, properties, action,detection and
treatment of poisoning.

6. POISON
Poison may be defined as any
substance which if administered or comes in
contact with a living being, produces ill health,
disease or death.
*Every drug in a high dose can be
poisonous

7. SOURCES:
Venom, toxins and poisons may be
originating from animals, microorganisms, plants
or chemicals may be,
1.ACUTE:A single large dose or multiple small
dose repeated at short intervals results in acute
poisoning.

8. 2.CHRONIC:
Small
doses repeated over a long period result in
chronic poisoning.signs and symptoms appear
gradually.
examples of chronic toxicity: Inhalation of certain
acid vapours at concentrations may, over long
periods of time, cause loss of tooth enamel,
eventually leading to extensive tooth decay.

9. II.SIGNS AND SYMPTOMS:
While signs and symptoms of poisoning can
vary depending on the type and other factors,
there are a few common symptoms to be aware
of:
Pain & headache, Vomiting,
Dizziness, Trouble breathing,
Disorientation, Feeling faint.

10. …,,,
Generally symptoms like hypotension and
dehydration due to diarrhoea and vomitting are
common,cardiac arrhythmias can occur
particularly from dugs like digitalis,
theophylline, amphetamine, ephedrine and
some antiarrhythmic drugs

11. DIAGNOSIS:
1.Consideration of poisoning in patients with
altered consciousness or unexplained symptoms
2.History from all available sources
3.Selective, directed testing
The first step of diagnosis of poisoning is to
assess the overall status of the patient. Severe
poisoning may require rapid intervention to treat
airway compromise or cardiopulmonary collapse.

12. TREATMENT:
No time should be lost in identifying the
exact poison. Treatment should be started
immediately with supportive measures.
Steps in the treatment of poisoning include,
1.STOP THE SOURCE OF POISONS:The patient
should be shifted away from the source of poison.

13. 2.LIMIT THE ABSORPTION OF POISON:
This depends on the route of entry,If taken
orally, vomitting may be induced or stomach wash
may be given to prevent further absorption of
poison
Cathartics or Bowl irrigation system may
also be used.

14. 3.SUPPORTIVE THERAPY:
Emergency stabilization of the cardio-
vascular and respiratory system is needed,
ABC-(Airway, Breathing, Circulation)
1. Airway should be cleared of any mucus by
suction to clear the air passages if needed.

15. …...
2.If breathing is depressed, artificial ventilat-
ion should be given.oxygen may be needed.
3.circulation: Circulatory status should be
assessed by pulse rate,blood pressure and urine
output
4.If the patient is in coma,nothing should be
given orally.If all comatose patient with signs of

16. …..
CNS depression administration of “coma cock
tail” is recommended,it includes
i.naloxone-2mg
ii.thiamine-100mg
iii.dextrose-50ml of 50% solution
All are given intravenously.

17. 4.SPECIFIC THERAPY: Specific antidotes,
antivenoms, antitoxins should be used,.
Agent causing toxicity
1.Paracetamol. -
2.morphine and other -
opioids
3.methanol. -
4.carbon monoxide. -
Antidotes
1.N-acetyl cysteine
2.Naloxone.
3.ethanol
4.oxygen

18. 5.OTHER MEASURES:
Forced diuresis, peritoneal
dialysis,haemodialysis,haemoperfusion, exchange
transfusion and such similar procedures are
carried out in certain cases of poisoning,only if
indicated

19. GENERAL MANAGEMENT:
1.GUT DECONTAMINATION:
It is done by by following three ways ,they
are emesis,stomach wash and purgatives.
i.EMESIS: vomitting can be induced with 20 to 30
ml of ipecac.It acts within 15 mins.
But if the poison is an corrosive agent or
petroleum product or if the patient is in uncons-
cious stage , vomitting should not be induced

20. ii.STOMACH WASH:
Washing the stomach with large amount of
water removes unabsorbed poison.
Stomach wash is also carried out in concious
patient only.
Warm water or saline may be used for lavage.
iii.PURGATIVES:It may help to speed up the
excretion of drugs from gut.Saline purgatives are
generally needed.eg:MgSO4 20-30gm given orally.

21. 2.MANAGEMENT OF RESPIRATORY FAILURE:
It is necessary to maintain a clear
airway.patient should be placed in semiprone
position. Oxygen may be given if there is hypoxia or
increased carbon dioxide on blood gas analysis.
3.MANAGEMENT OF CIRCULATORY FAILURE:
In presence of hypotension, foot end of the
bed should be elevated.Vassopressors like
dopamine, phenylephrine or methoxamine may be
used.

22. 4.ANTIDOTES:
An antidote is the substance which
antagonizes and overcomes the effect of
poison.Unfortunately specific antidotes are
available only for a few toxins.
According to the mode of action antidotes are
classified into three types, they are,
I.PHYSICAL ANTIDOTES:Act by reducing the
adsorption of poison. eg:activated charcoal
adsorbs. Alkaloids

23. 2.CHEMICAL ANTIDOTES:
These act by forming complex with poison.
eg:acetic acid reacts with alkaline.
3.PHARMACOLOGICAL ANTIDOTES:
These antidotes are compete for binding to
the same receptors or sites where the toxins
binds.eg: naloxone for morphine.

24. SNAKE BITE TREATMENT:
All over the world snake bites are respons-
-ible for 30,000 to 40,000 deaths every year.In,India
2 lakh people are bitten by snakes every year of
which about 16,000 die.vipers, cobra and kraits are
common poisonous snakes.
SIGNS AND SYMPTOMS:.
The signs and symptoms of systemic activity
appear in about half an hour,..

25. Common symptoms:
In all cases of snake bite,the patient is in,..
Semiconcious state, Cold,
Clammy skin, feeble pulse,
Rapid and shallow brearthing, pain,
Swelling, Burning
Discolouration of site,. Oozing blood,..etc,

26. …...
1.Elapid bite(cobra,kraits,.)- neurotoxic
2.Viper bite. -haemotoxic
3.Sea snakes. -
hydrophids/myotoxic
TREATMENT: I.FIRST AID:1.Reassurance
2.Immobilise the bitten part.Measures like local
incision,suction,application of ice are all found to
be harmful and no more recommended.

27. 2.SPECIFIC THERAPY:
Antisnake venom(ASV) is indicated in presece
of signs of systemic envenomisation.Dose of
antivenom varies,
i.Mild envenomisation - 3 to 5 vials
ii.moderate envenomisation -5 to 10 vials
iii.severe envenomisation -10 to 20 vials
Infusion should be done after test dose.clean the
bite site with providence iodine.

28. FOOD POISONING:
Food poisoning can occur on
consumption of food that is contaminated with
microorganisms,toxins or chemicals.
CAUSES FOR FOOD POISONING:
1.Microorganisms: Bacteria,fungi,protozoa and
viruses
2.Toxins: in certsin fish, plants & mushrooms.
3.Chemicals.

29. SIGNS AND SYMPTOMS:
Nausea
Vomitting
Abdominal pain
Fever
Weakness and Diarrhoea are the common
symptoms
Other symptom depends on causative agent.

30. REFERENCES:
1.Book;Phamacology,
Author;Padmaja udayakumar
2.https://www.msdmanuals.com/professional/
injuries-poisoning/poisoning/general-principles-of-
poisoning

31. THANK YOU