Onset of FFI usually occurs between the ages of 30 and 60. The disease typically goes through a four-stage progression. In the first stage, which lasts about four months, the individual shows increasing lack of sleep and also develops phobias and/or panic attacks that become more and more intense. In the second stage, which lasts for about five months, insomnia becomes more severe and is accompanied with hallucinations that may be auditory or visual. The phobias and panic attacks further intensify, accompanied by sweating and agitation. Loss of appetite and weight loss may also occur in this stage. The duration of the third stage is approximately three months. The patient can no longer sleep. There is severe incontinence and weight loss. The previous symptoms worsen, and there are signs of diminished mental capacity and possibly early signs of dementia. The final or fourth stage lasts about six months. Dementia worsens, as well as weight loss. The patient becomes mute and unresponsive to stimuli. The patient eventually falls into coma and dies from sleep deprivation and other complications. At present there is no treatment for FFI and research toward a therapy has not been promising.