Poisoning & drug overdose

1. Poisoning & Overdose
• Substance which endangers life by severely affecting
one or more vital functions, is known as poison.
• Poisoning may result from drug overdose or
ingestion of poisonous substance.
• Poisoning may result from:
• Large dose of drug
( It is dose which distinguishes a drug from poison)
• Household & industrial chemicals, insecticides
(organophosphate poisoning)

2. • All patients who show features of poisoning
should be admitted to hospital even those who
have taken poison with delayed action.
Examples of delayed action poison are
acetylsalicylic acid, iron, paracetamol, etc
Steps to be taken for handling poisoning case:
• Identify the poison & its dose consumed.
• If there is antidote for it then use it.
(can call to poison centre)
• If there is no antidote treat symptomatically.

3. Treatment of poisoning
1. Resuscitation (ABCDE approach)
2. Risk Assessment
3. Supportive Care and Monitoring
4. Investigations
5. Decontamination
6. Enhanced Elimination
7. Antidotes
8. Disposition

5. Principles for treatment of poisoning
1. Removal of the exposed poison
• Taking the patient to fresh air (for inhaled poison)
• Washing the skin & eyes (poisoning through surface
like organophosphate poisoning)
• Inducing emesis or doing gastric lavage (for
ingested poison)
2. Prevention of absorption of ingested poison
• Activated charcoal 50g (25g in children)
• OR Universal Antidote (Charcoal: Tannic acid:
Manganese oxide in 2:1:1 ratio)

7. 3. Accelerated elimination of the poison
• Increasing urine output by the use of diuretics
like furosemide, mannitol, etc
• Adjusting the reaction of urine (weakly acidic
drug excrete fast in alkalization & basic drug in
acidification)
• Dialysis or Hemoperfusion ( passage of blood
through a column of charcoal or adsorbent resin)

9. 4. Specific Antidotes
Drug overdose/Poison Antidote
Paracetamol N-acetyl cysteine
Opoids Naloxone
Organophosphate, carbamates Atropine, Pralidoxime
Belladona(Atropine) Poisoning Physostigmine
Mushroom Poisoning Atropine
Benzodiazepine Flumazenil
Arsenic poisoning Dimercaprol
Iron Desferoxamine
Warfarin Vitamin K
Heparin Protamine sulfate
Copper, gold, lead, mercury, zinc Penicillamine
Beta blocker Adrenaline

10. 5. Monitoring Vital signs & supportive measures
• Maintenance of Airway
• Maintenance of Breathing
• Maintenance of blood Circulation
• Unconscious patients may develop hypothermia so they
must be wrapped with blanket to conserve body heat
• For prolong or recurrent convulsions diazepam i.v. may
be used
6. Prevention of repeated poisoning
• Follow up & psychiatric counseling in case of suicidal
poisoning
• Taking preventive measures for repeated exposure of
poison in case of accidental poisoning e.g: labeling &
locking of poison, keeping drugs out of reach of children

11. Emesis
• Emesis or vomiting is the forceful expulsion of the
contents of the gastrointestinal system out through the
mouth.
• It is a mechanism of the body to get rid of noxious
substances that have been ingested, rather than
allowing them to be retained and absorbed by the
intestine.
• There are two medullary centres of vomiting in the
brain known as the sensory “chemoreceptor trigger
zone (CTZ)” and the integrative centre.
• Drugs used for emesis:
• Apomorphine
• Ipecacuanha

12. Activated Charcoal
• Activated charcoal or activated carbon is a charcoal that has
been heated or treated to increase its adsorptive power &
expand its surface area. It is a medication used to
treat poisonings occurred by mouth.
• For effective use it must be used within a short time of the
poisoning occurring, typically an hour.
• Dose: 50 g (adults) or 1g/kg (child)
• It may be taken by mouth or given by a nasogastric tube.
Other uses include inside hemoperfusion machines.
• Mechanisms of action:
• Active charcoal binds the poison and prevents its absorption
by the gastrointestinal tract.
• Binding is reversible so a cathartic such as sorbitol may be
added as well.
• It interrupts the enterohepatic and enteroenteric
circulation of some drugs/toxins and their metabolites.

13. CAUTION!
• Do not try Activated Charcoal for:
• Hydrocarbons and Alcohols: Ethanol, Isopropyl
Alcohol, Ethylene glycol, methanol
• Metals: Lithium, Iron, Potassium, Lead, Arsenic,
Mercury
• Corrosives: Acids, Alkali

14. “Everything is poisonous, there is nothing
that is non-poisonous. Solely the dose
separates a poison from a remedy.”
-Paracelsus, Father of Toxicology