I am a Registered Polysomnography Tech and work in
a Sleep Center. I can only tell you about narcolepsy in humans.
People with narcolepsy will instantly fall into REM
sleep. During REM sleep you dream, and you loose muscle tone. This is mother
nature's way of preventing you to act out your dreams. Because of the loss of
muscle tone, people can collapse (cataplexy). In humans this condition is
treated with stimulants like Provigil (drug of choice) or Ritalin.
It would be fun to study a horse, but I doubt they
would let me bring it into the hospital, and it wouldn't fit into our beds
anyway. HA HA!
Anyway, I am not sure about the normal sleep
architecture of a horse. I would think that the horse has very little REM, since
they sleep standing up. I am not sure if there is any research about the sleep
of horses.
Also not sure if horses can be treated with
medication. How did the vet arrive at this diagnosis? The only way to prove
narcolepsy in humans is a sleep study.