Unconsciousness is when a person is unable to respond to people and other stimuli around him or her. Often, this is called a coma or being in a comatose state.

Other changes in awareness can occur without becoming unconscious. Medically, these are called "Altered Mental Status" or "Changed Mental Status." They include sudden confusion, disorientation, or stupor.

Unconsciousness and any other SUDDEN change in mental status must be treated as a medical emergency.

If someone is awake but less alert than usual, ask a few simple questions -- What is your name? What is the date? How old are you? If the person doesn't know or answers incorrectly, then his or her mental status is diminished.

Being asleep is not the same thing as being unconscious. A sleeping person will respond to loud noises or gentle shaking -- an unconscious person will not.

An unconscious person cannot cough or clear his or her throat. This can lead to death if the airway becomes obstructed.

• Unconsciousness can be caused by virtually any major illness or injury, as well as substance abuse and alcohol use.
• Brief unconsciousness (or fainting) is often caused by dehydration, low blood sugar, or temporary low blood pressure. However, it can also be caused by serious cardiovascular or neurologic illness. Your doctor will determine if you need to be tested for such underlying disorders.
• Other causes of fainting include straining during a bowel movement, strenuous coughing, or hyperventilating.

• Unresponsiveness (does not awaken when spoken to, touched, or otherwise stimulated)
• Unconsciousness may be brief and temporary (fainting) or prolonged
• Disorientation
• Light-headedness
• Palpitations
• Headache
• Drowsiness
• Stupor

1. Call or instruct someone to call 911.
2. Check the person's airway, breathing, and circulation frequently. If necessary, begin rescue breathing and CPR.
3. If the person is breathing, and a spinal injury is NOT suspected, and he is lying on his back, carefully roll him toward you onto his side. Bend the top leg so both hip and knee are at right angles. Gently tilt the head back to keep the airway open. If breathing or circulation stops at any time, roll the person on to his back and begin CPR.
4. If a spinal injury is suspected, leave the person as he was found (as long as he is breathing freely). If spinal injury is suspected and the person vomits, "log roll" the person to his side. Support the neck and back to keep head and body in the same position while you roll.
5. Keep the person warm until medical help arrives.
6. If you witness a person fainting, try to prevent him or her from falling. Lie the person flat on the floor and elevate the feet about 12 inches.
7. If fainting is likely due to low blood sugar, have the person eat or drink something sweet when he or she fully regains consciousness.

• DO NOT give an unconscious person any food or drink.
• DO NOT leave the person alone.
• DO NOT place a pillow under the head of an unconscious person.
• DO NOT slap an unconscious person's face or splash water on the face to try to revive him.

Call 911 if the person:

• Is not breathing.
• Does not regain consciousness quickly (within a couple of minutes).
• Fell from a height or has been injured, especially if bleeding.
• Has diabetes.
• Is pregnant or is over 50 years old.
• Feels chest pain, chest pressure, chest discomfort, or has a pounding or irregular heartbeat.
• Can't speak, has vision problems, or can't move a limb.
• Has convulsions, tongue trauma, or loss of bowel control.

• People with known medical conditions, such as diabetes, should always wear a medical alert tag or bracelet.
• Avoid situations where your blood sugar level gets too low.
• Avoid standing in one place too long without moving, especially if prone to fainting.
• If you feel like you are about to faint, lie down or sit with your head bent forward between you knees.