The incidence and prevalence of narcolepsy is no different from that of Multiple Sclerosis or Parkinson's disease. However due to lack of public awareness of the condition the diagnosis is seldom established.
Narcolepsy is observed in all racial and ethnic groups the world over. It affects both males and females equally. It is believed to affect 1 in 1,000 individuals of both sexes and all races.
But prevalence rates are known to vary among populations. Studies on the epidemiology of narcolepsy show an incidence of 0.2 to 1.6 per thousand in European countries, Japan and the United States. About one in 2,000 Americans is estimated to be suffering this disorder. However the exact prevalence rate remains uncertain and the disorder may affect a larger segment of the population than is currently estimated.