Sleep Apnea is a common sleeping disorder that affects over 25 million Americans. Due to the complex nature of sleep apnea, and the human body, neither an effective nor comfortable treatment option for sleep apnea has been developed. Accordingly, we describe a novel alternative to current sleep apnea therapies, including CPAP therapy. A comfortable device for treating sleep apnea incorporates a mask, a flexible hose and a chamber for collecting expired air containing CO2. A sensor detects apnea and a control system automatically adjusts the amount of rebreathed CO2 minimize apnea and also minimize arousal.