Decreased Level of Consciousness (LOC) is caused by global depression of the brain’s reticular system and may be a
consequence of almost any drug or toxin. In patients with a recent history of illicit substance use, decreased LOC can be a
result of direct central nervous system (CNS) toxicity (eg. alcohols, sedative-hypnotic agents, narcotics, mushrooms, serotonin
syndrome), secondary metabolic or CNS toxicity (eg. seizures/post-ictal, hypoxaemia, hyponatraemia, hypoglycaemia) or
non-toxicological issues (eg. head injury, trauma).
Coma or stupor may be preceded by drowsiness, yawning, dizziness, sweating, pallor, blurred vision, nausea or confusion.
Airway and respiratory compromise is the most emergent consequence of decreased LOC, however other complications such
as hypotension and hypo- or hyperthermia must also be anticipated and addressed.
Other pre-hospital guidelines