Clinical presentation

The effects of stimulant drug poisoning are caused by the relative effects on synaptic neurotransmitter concentrations, mainly dopamine, noradrenaline and serotonin. Metamfetamine is more adrenergic and dopaminergic, and poisoning usually presents with sympathomimetic toxidrome. MDMA has predominantly serotonergic effects and can present with a serotonergic toxidrome.

Effects of stimulant drug poisoning, many of which can be life threatening, include:

• cardiovascular effects
  • tachycardia, arrhythmias
  • hypertension; if severe, can cause aortic or carotid dissection or mesenteric ischaemia
  • acute coronary syndrome, myocardial ischaemia or infarction
  • hypotension (with severe sympathomimetic toxidrome), myocardial depression, pulmonary oedema
• CNS effects
  • excitation—anxiety, euphoria, agitation, tachypnoea, delirium, seizures
  • acute behavioural disturbance—aggression, violence, psychosis
  • thrombotic and haemorrhagic strokes, intracranial haemorrhage
• neuromuscular effects—hyperreflexia, tremor
• autonomic effects
  • hyperthermia (temperature more than 39ºC or rapidly rising)—if severe can cause multiorgan failure
  • sweating, flushing, pallor, mydriasis
• metabolic effects
  • hyponatraemia—resulting from both syndrome of inappropriate secretion of antidiuretic hormone (SIADH) and excessive water intake; severe hyponatraemia can cause cerebral oedema and seizures
  • hypokalaemia, hyperglycaemia, lactic acidosis
• gastrointestinal effects—nausea, vomiting, diarrhoea
• other effects
  • rhabdomyolysis—occasionally causing secondary kidney failure
  • respiratory—pneumothorax, pneumomediastinum.