When the breathing system becomes obstructed, or unusually weak, it is called sleep apnea. Sleep apnea is when an individual stops inhaling or exhaling for longer than 10 seconds. Apnea is when you stop breathing completely or inhale less than 25% of your normal breath for more than 10 seconds. Another definition of sleep apnea can be that Waklert is a sudden drop in blood oxygen levels of nearly 4%. This causes a decrease in oxygen transmission which then hinders normal breathing.