Nitrogen narcosis limits the depth when breathing nitrox mixtures. Nitrogen narcosis limits the depth reachable by underwater divers when breathing nitrox mixtures. Breathing at depth can cause nitrogen narcosis and oxygen toxicity. Rapid compression potentiates narcosis owing to carbon dioxide retention. Nitrogen narcosis or oxygen toxicity had caused him to lose his mouthpiece and drown. Nitrogen narcosis is a hazard when diving. It causes nitrogen narcosis in the diver, so its use is limited to shallower dives. Xiao Kai recounts how Guo Dong disappeared after saving Dr. Gao from nitrogen narcosis. This may be due to a dissociation of the subjective and behavioural effects of narcosis. Unfortunately, the wearer is still susceptible to nitrogen narcosis and the bends. "Atropa belladonna" is also toxic to many domestic animals, causing narcosis and paralysis. Narcosis is a problem when breathing gases at high pressure. In America, however, there was less enthusiasm for chloroform narcosis. Due to its perception-altering effects, the onset of narcosis may be hard to recognize. As depth increases, so does the pressure and hence the severity of the narcosis.