Narcolepsy in the Mini Horse

Narcolepsy is rare, but does occasionally occur in the miniature horse.  This condition results from
an imbalance of chemicals in the brain that control sleep and wakefulness.

The University of Wisconsin did a survey and found that narcolepsy was a "rare but distinct
syndrome in the Miniature Horse."

It is more common in foals, and in most instances, it disappears as they reach adulthood.

The symptoms range from mild muscle weakness to full collapse. It may occur while grooming,
clipping, bathing or petting the horse, and rarely happens during a workout.

Episodes tend to occur during brain wave rhythms called REM brain. Tests can be done to
determine if the horse with these symptoms has narcolepsy, and antidepressants such as
imipramine can be given which suppress REM sleep.
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