Up to 3% of adults have sleep terrors and exhibited behavior of this parasomnia can range from mild to extremely violent. This is very prevalent in those who have violent post-traumatic stress disorder (PTSD). They typically occur in stage 3 sleep. Sleep-related eating disorder (SRED)
The Diagnostic and Statistical Manual of Mental Disorders (DSM-V) classifies sleep-related eating disorder under sleepwalking, while ICSD classifies it as NREM-related parasomnia. It is conceptualized as a mixture of binge-eating behavior and arousal disorder. Thereby, preferentially high-caloric food is consumed in an uncontrolled manner. However, SRED should not be confused with nocturnal eating syndrome, which is characterized by an excessive consumption of food before or during sleep in full consciousness. Since sleep-related eating disorders are associated with other sleep disorders, successful treatment of the latter can reduce symptoms of this parasomnia. Rapid eye movement (REM)-related parasomnias
REM sleep behavior disorder
Unlike other parasomnias, rapid eye movement sleep behavior disorder (RBD) in which muscle atonia is absent is most common in older adults. This allows the individual to act out their dreams and may result in repeated injury—bruises, lacerations, and fractures—to themselves or others. Patients may take self-protection measures by tethering themselves to bed, using pillow barricades, or sleeping in an empty room on a mattress. Besides ensuring the sleep environment is a safe place, pharmacologic therapy using melatonin and clonazepam is also common as a treatment for RBD, even though they might not eliminate all abnormal behaviours. Before starting a treatment with clonazepam, a screening for obstructive sleep apnea should performed.
However, clonazepam needs to be manipulated carefully because of its significant side effects, i.e., morning confusion or memory impairment, mainly in patients with neurodegenerative disorders with dementia.Demographically, 90% of RBD patients are males, and most are older than 50 years of age. However, this prevalence in males could be biased due to the fact that women tends to have a less violent type of RBD, which leads to lower reports at sleep centres and different clinical characteristics. While men might have more aggressive behaviour during dreaming, women have presented more disturbance in their sleep. RBD may be also influenced by a genetic compound, since primary relatives seem to have significantly more chance to develop RBD compared with non-relatives control group.Typical clinical features of REM sleep behavior disorder are:

Male gender predilection
Mean age of onset 50–65 years (range 20–80 years)
Vocalisation, screaming, swearing that may be associated with dreams
Motor activity, simple or complex, that may result in injury to patient or bed-partner
Occurrence usually in latter half of sleep period (REM sleep)
May be associated with neurodegenerative disease Acute RBD occurs mostly as a result of a side-effect in prescribed medication—usually antidepressants. Furthermore, substance abuse or withdrawal can result in RBD.Chronic RBD is idiopathic, meaning of unknown origin, or associated with neurological disorders. There is a growing association of chronic RBD with neurodegenerative disorders—Parkinsons disease, multiple system atrophy (MSA), or dementia—as an early indicator of these conditions by as much as 10 years.