MedlinePlus Medical Encyclopedia: Consciousness

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Consciousness - decreased

Contents of this page:
Alternative Names Definition Considerations Causes	Home Care When to Contact a Medical Professional What to Expect at Your Office Visit

Alternative Names

Stuporous; Mental status - decreased; Loss of alertness; Decreased consciousness; Alertness - decreased; Changes in consciousness; Obtundation; Coma

Definition Return to top

Decreased consciousness is reduced alertness or awareness.

Considerations Return to top

A persistent coma is called vegetative state.

Causes Return to top

Many conditions can cause decreased consciousness, including:

Alcohol or drug intoxication
Arrhythmia
Central nervous system diseases
Decreased oxygen (hypoxia)
Diabetic coma
Electrolyte imbalance
Exposure to heavy metals or hydrocarbons
Extreme fatigue or sleep deprivation
Ketoacidosis
Head trauma
Heart failure
Hypoglycemia
Infection
Low blood pressure (hypotension)
Metabolic problems
Seizures such as those related to epilepsy
Shock
Stroke

Home Care Return to top

A decrease in consciousness almost always require a doctor's attention, except perhaps when due to alcohol intoxication, simple fainting, or a previously recognized seizure disorder.

See the article on seizures for tips on how to care for a person who is having a seizure.

Persons with epilepsy or other seizure disorder should carry a Medic-Alert bracelet or pendant stating that they have the condition. Avoid any circumstance that has previously triggered a seizure.

When to Contact a Medical Professional Return to top

See medical help if someone has unexplained, decreased consciousness. Call your local emergency number (such as 911) if normal consciousness does not return quickly.

What to Expect at Your Office Visit Return to top

The doctor will perform a physical examination. The exam will include a detailed look at the cardiovascular and nervous system.

The health care team will ask questions about the person's medical history and symptoms, including

Time pattern
- When did the decreased consciousness occur?
- How long did it last?
- Has it ever happened before? If so, how many times?
- Did the person behave the same way on previous episodes?
Medical history
- Does the person have known epilepsy or seizure disorder?
- Does the person have diabetes?
- Has the person been sleeping well?
- Has there been a recent head injury?
Other
- What medications does the person take?
- Does the person habitually use alcohol or drugs?
- What other symptoms are present?

Tests that may be done include:

Complete blood count or blood differential
Electrolyte panel
CT scan or MRI of the head
ECG
EEG
Chest x-ray
Urinalysis

Treatment depends on the underlying cause of the decreased consciousness.

Update Date: 8/6/2007

Updated by: Daniel Kantor, M.D., Director of the Comprehensive MS Center, Neuroscience Institute, University of Florida Health Science Center, Jacksonville, FL. Review provided by VeriMed Healthcare Network.

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