drugs of abuse

Question 1

In which patients presenting at A&E should you consider drugs of abuse in?

Answer 1

You should consider drugs of abuse in all patients that present in A&E

in particular you need to consider it in any patient who is

• difficult or uncooperative
• cannot remember what they are doing or explain what is wrong
• violent / aggressive

Question 2

what are the 4 classifications of drugs of abuse?

Answer 2

stimulants
sedatives/ dissociative
hallucinogens
cannabinoids

Question 3

what common stimulants are used?

Answer 3

amphetamines - eg. speed, MDMA
cocaine - cocaine hydrochloride (snorting) or cocaine base (crack - smoking)
piperazines
cathinone - naturally occurring and has been chewed for centuries
synthetic cathinone - mcad/ meow meow

Question 4

what common sedatives are used?

Answer 4

alcohol
opiates/ opioids - morphine, heroin, fentanyl, carfentanyl
GHB/GHL
ketamine

Question 5

what common hallucinogens are used?

Answer 5

magic mushrooms
LSD
phenylethylamines
synthetic tryptamines

Question 6

what common cannabinoids are used?

Answer 6

CB1 and CB2 receptor antagonists

Question 7

what are the features of stimulants?

Answer 7

Increased alertness and self confidence
Euphoria and extrovert behaviour
Increased talkativeness with rapid speech
Loss of desire to eat or sleep
Dilate pupils, tachycardia, hypertension
Tremor, hypertonic, hyperreflexia, convulsions
Agitation, paranoid delusions, hallucinations
Direct rhabdomyolysis - not from long lie
Hyperthermia
Cardiac arrhythmias and cardiomyopathy
Intracerebral; and subarachnoid haemorrhage
Acute renal failures
Fulminant hepatic failure

Question 8

how is stimulant overdose managed?

Answer 8

• supportive measures
• diazepam 10mg IV repeated as necessary
• if there is any hyperthermia then use active cooling with cooled fluids and ice packs. if needed use dantroline which causes reduced contraction in skeletal muscle cells

Question 9

what are the features of sedative overdose?

Answer 9

Sedation 
Suppression of cough reflex 
Miosis 
Constipation 
Pulmonary oedema 
Cardiac construction abnormalities 
Coma respiratory depression - with low pO2 and high PCO2 - respiratory acidosis

Question 10

how is sedative overdose managed?

Answer 10

ABC assessment is vital
naloxone - opiate receptor competitive antagonist. this has a short half life of 30-60 minutes and is relatively safe so should be administered even if you are not sure what has been taken
methadone - this is a synthetic opiate which is used as a heroin substitute with a long half life of 20-50 hours. it is prescribed to mitigate withdrawal with the intention of weening. (controversial as many patients remain on heroin alongside and often it is never tapered down to 0)

Question 11

what are the features of hallucinogens?

Answer 11

Tachycardia 
Hypertension 
Agitation and aggression 
Visual and auditory hallucinations
Seizures 
Increased CK activity - rhabdomyolysis

Question 12

what are the features of cannabinoids?

Answer 12

Euphoria
Distorted and heightened images, colours and sounds
Visual and auditory hallucinations ‘confusion and depersonalisation
Panic
Psychosis

Features of synthetic canaboids:
Nausea and vomiting 
Sinus tachycardia 
Coma 
Acute respiratory failure 
Agitation, paranoia 
Seizures 
Rarely MI, stroke or AKI

Question 13

what is the management of cannabinoid overdose?

Answer 13

supportive management
benzodiazapines
security