A poison is any substance — whether liquid, solid, or gas — that produces harmful physiological effects or tissue injury when it enters the body through ingestion, inhalation, injection, or absorption across the skin or mucous membranes.

Globally, poisoning remains a major public-health problem, particularly in low- and middle-income countries where:

• pesticides are widely available,

• fuels are stored in drink containers,

• medications are easily accessible,

• and traditional medicines are commonly used.

In many East African settings, the most frequent causes of poisoning include:

• pesticides (especially organophosphates),

• hydrocarbons (kerosene),

• medications,

• contaminated foods,

• snake and envenomation-related toxins.

Poisoning may be:

• Accidental — especially in children

• Intentional — self-harm in adolescents/adults

• Occupational — agricultural or industrial exposure

Always suspect poisoning in any sudden unexplained illness in a previously healthy person.

Common Sources of Poisoning

1. Household Agents

• Organophosphates (e.g. malathion insecticides)

• Rat poison

• Disinfectants and bleach

• Hydrocarbons (kerosene, petrol, turpentine)

2. Medications

• Analgesics (paracetamol, aspirin)

• Anticonvulsants (carbamazepine)

• Hematinics (iron tablets)

• Antipsychotics (major tranquilizers)

• Sedatives and benzodiazepines

• Herbal and traditional remedies

3. Food Poisoning

• Toxic mushrooms

• Contaminated food

• Bacterial toxins

4. Recreational / Illicit Drugs

Sympathomimetic agents

• Cocaine

• Amphetamines

• LSD

• PCP

5. Agricultural Chemicals

Cholinergic toxins

• Organophosphates

• Carbamates

Risk Factors

Patient Factors

• Children under 5 years

• Psychiatric illness

• Substance abuse

• Suicide attempts

• Elderly with polypharmacy

• Chronic liver or kidney disease

Environmental Factors

• Unsafe storage of chemicals

• Unlabeled containers

• Agricultural occupation

• Traditional medicine use

• Low literacy

Signs and Symptoms

Symptoms depend on the toxidrome (pattern of toxicity) rather than the specific poison.

1. General Symptoms

• Nausea

• Vomiting

• Abdominal pain

• Dizziness

• Weakness

2. Sympathomimetic Toxidrome

(Stimulant poisoning)

3. Cholinergic Toxidrome

(Organophosphate poisoning)

SLUDGE syndrome

• Salivation

• Lacrimation

• Urination

• Diarrhea

• Gastrointestinal cramps

• Emesis

Additional:

• Miosis

• Bradycardia

• Bronchospasm

• Respiratory failure

4. CNS Depressant Toxidrome

• Reduced consciousness

• Slow breathing

• Hypotension

• Coma

5. Anticholinergic Toxidrome

• Dry skin

• Hot flushed skin

• Dilated pupils

• Delirium

• Urinary retention

Diagnostic Criteria

Diagnosis is primarily clinical.

A patient is considered poisoned if:

1. Sudden unexplained illness

2. Exposure history or suspicion

3. Toxidrome present

4. Supporting laboratory abnormalities

Investigations

Baseline Tests (All Patients)

• Random blood glucose

• Serum electrolytes

• Renal function tests

• Liver function tests

• Full blood count

• Arterial blood gas

• ECG monitoring

Sympathomimetic Toxidrome Work-up

• ECG

• Creatine kinase

• Coagulation profile (PT/PTT/INR)

• Serum osmolality & osmolar gap

• Toxicology screen

• Abdominal X-ray (drug packets)

Additional Tests Depending on Poison

• Drug levels (paracetamol, salicylate, lithium)

• Chest X-ray (aspiration)

• CT brain (persistent coma)

Treatment

Management follows a holistic structured approach

Non-Pharmacological Management

1. Resuscitation (Always First)

• Airway protection

• Oxygen therapy

• IV access

• Cardiac monitoring

• Correct hypoglycemia

• Control seizures

2. Decontamination

• Remove contaminated clothes

• Wash exposed skin

• Activated charcoal if indicated

• Gastric lavage (selected life-threatening cases)

3. Supportive Care

• IV fluids

• Temperature control

• Ventilatory support

• Observation 4–24 hrs minimum

Pharmacological Management

1. Antidotes (If Known)

2. Symptom-Based Therapy

• Benzodiazepines for seizures

• Vasopressors for shock

• Sodium bicarbonate for acidosis

• Dialysis for dialyzable toxins

3. Psychosocial Intervention

• Suicide risk assessment

• Psychiatric referral

• Counseling

• Family education

Prevention

Do’s

• Store chemicals safely

• Use child-resistant containers

• Keep original packaging

• Read labels carefully

Don’ts

• Do not transfer chemicals to drink bottles

• Do not remove labels

• Do not leave containers open

• Do not call medicine sweets

• Avoid taking medication in front of children