What are some of the symptoms of carbon monoxide poisoning?

The symptoms caused by carbon monoxide poisoning are easily overlooked because they are often like the flu. With mild exposure, most people experience headaches, fatigue and nausea. Medium exposure can cause a severe throbbing headache, drowsiness, disorientation, confusion and an accelerated heart rate. Extreme exposure can lead to unconsciousness, convulsions, heart or respiratory failure, coma and even death.