question:  What is the purpose of paraoxynebutal?
context: [Transcriber's Note: This etext was produced from Galaxy Science Fiction November 1951. Extensive research did not uncover any evidence that the U.S. copyright on this publication was renewed.] Rootless and footloose, a man in space can't help but dream of coming home. Flight Officer Robert Craig surrendered the tube containing his service record tapes and stood waiting while the bored process clerk examined the seal. "Los Angeles, eh? "No specific destination," supplied the man as he punched a key on a small instrument, "Air-lock ahead and to your right. "Insert your right arm into the instrument on the central table," commanded the same voice he had heard before. "With the help of paraoxylnebutal," supplied the captain. Short of Gravitational conditioning, there is nothing to stop you from going to Terra." Your body is conditioned to a normal state of free fall, or at best to a state of acceleration." That is why all spacemen carry PON, paraoxylnebutal, with them. It helps suppress certain physiological reactions to an entirely new set of conditions. Channels of the ear, for example. They play an important part in our awareness of balance. Returning to gravity is rather frightening at first." "Do you know what sailors of ancient times meant by 'sea legs?'" asked Wyandotte. But even if he could accept the psychologist's authority for the cumulative effect of a gravity system, he could not understand the unspoken warning he felt underlying all that the man said. If the service needs men so badly, let them get somebody else. You will be given a very liberal supply of PON—which you will definitely need. On the eighth day, two attendants, who showed the effects of massive doses of PON to protect themselves from the centrifugal force, had to carry a man out of the tank. "How ... how do they know when you ought ... to come out?" "Blood pressure. "Can't they ... drop it down continuously?"
output:  It helps people adjust to changes in gravity
options:  It relaxes the sympathetic nervous system  It puts a human to sleep for up to 12 days  It helps people adjust to changes in gravity  It opens the airways to allow for easier breathing