<unk>  can result from a variety of factors, including alterations in the chemical environment of the brain, insufficient oxygen or blood flow in the brain, and excessive pressure within the skull. The level of consciousness may decline abruptly or slowly, or it may increase and decrease intermittently. 
Life threatening causes of<unk>  include malignant hypertension, myocardial infarction, rabies and sepsis. Other common causes of<unk>  include alcohol withdrawal, dehydration, electrolyte disturbance and hypoglycemia.
Altered mental status
Altered state of consciousness
Somnolence
Snatiation
Psychomotor agitation
Pallor
Sedation
Myoclonus