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Acute Care Advisor 2017.1 Copyright © 2017 RelayHealth, a division of McKesson Technologies Inc. All rights reserved.

What is altered level of consciousness?


Altered level of consciousness (ALOC) means that you are not as awake, alert, or able to understand or react as you are normally. Causes of ALOC include:

  • A head injury

  • Medicines

  • Alcohol or drugs

  • Dehydration

  • Infection

  • Fever

  • Dangerously low body temperature (hypothermia)

  • Diseases such as diabetes and thyroid disease


Different levels of ALOC include:

  • Lethargic, which means you are drowsy and less aware or less interested in your surroundings

  • Somnolent, which means you are sleeping unless someone or something wakes you up. You can usually talk and follow directions, but you may have trouble staying awake.

  • Stupor, which means you are in a deep sleep unless something loud or painful wakes you up. You may not be able to talk or follow directions well, and you will fall back to sleep when left alone.

  • Coma, which looks as if you are asleep, but you can’t be awakened at all

  • Confusion, which means you are easily distracted and may be slow to respond. You may not know who or where you are or the time of day or year.

  • Delirium, which means you have severe confusion and disorientation and may have delusions (belief in things that are not real) or hallucinations (sensing things that are not real). The degree of confusion may get better or worse over time.