Multiple reasons: Can be as simply as anxiety to ; hypoglycemia (low blood sugar); severe pain; and low blood oxygen levels from any of the following conditions: heart attack; heat exhaustion; pulmonary embolus (blockage of an artery within the lung due to a blood clot); heavy or internal bleeding, dehydration, or pneumonia; severe infection; or drug overdose that reduces heart function or blood pressure.
Answered 10/30/2013
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A doctor has provided 1 answer
A doctor has provided 1 answer
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