People with sleep paralysis are not able to move their body or limbs when falling asleep or waking up. Brief episodes of partial or complete skeletal muscle paralysis can occur during sleep paralysis. Sometimes sleep paralysis runs in families, but the cause of sleep paralysis is not known. This disorder is not harmful, but people experiencing sleep paralysis often are fearful because they do not know what is happening. An episode of sleep paralysis often is terminated by sound or touch. Within minutes, the person with sleep paralysis is able to move again.
Impaired sleep-related penile erections
This disorder occurs among men who are unable to sustain a penile erection during sleep that would be sufficiently rigid enough to engage in sexual intercourse. Men usually experience erections as a part of REM sleep, and impaired sleep-related erections may indicate physiological impotence.
Sleep-related painful erections
Erections are a normal component of REM sleep for men. In rare cases, however, erections become painful and cause a man to wake up. The treatment of sleep-related painful erections may involve drugs that suppress REM sleep (some antidepressants, for example).
REM sleep cardiac arrhythmias
A cardiac arrhythmia is a change from the normal rate or control of the hearts contractions. People who have coronary artery disease and whose blood oxygen is lowered by sleep-disordered breathing may be at risk for arrhythmias, which take place during REM sleep. Continuous positive airway pressure (CPAP) treatment may reduce this risk.
REM sleep behavior disorder (RBD)
People with rapid eye movement (REM) sleep behavior disorder act out dramatic and/or violent dreams during REM sleep. REM sleep usually involves a state of sleep paralysis (atonia), but people with this condition move the body or limbs while dreaming. Usually, RBD occurs in men aged 60 and older, but the disorder also can occur in women and in younger people. In the diagnosis and treatment of RBD, potentially serious neurological disorders must be ruled out. Polysomnography (sleep tests) and drug treatments also can be involved in the diagnosis and treatment of this disorder.
Sleep bruxism involves the involuntary, unconscious, excessive grinding or clenching of teeth during sleep. It may occur along with other sleep disorders. Sleep bruxism may lead to problems including abnormal wear of the teeth and jaw muscle discomfort. The severity of bruxism can range from mild cases to severe cases that involve evidence of dental injury. In some cases, bruxism can be prevented with the use of a mouth guard. The mouth guard, supplied by a dentist, can fit over the teeth to prevent teeth from grinding against each other.
Sleep enuresis (bedwetting)
In this condition, the affected person is unable to maintain urinary control when asleep. There are two kinds of enuresis -- primary and secondary. In primary enuresis, a person has been unable to have urinary control from infancy onward. In secondary enuresis, a person has a relapse after previously having been able to have urinary control. Enuresis can be caused by medical conditions (including diabetes, urinary tract infection, or sleep apnea) or by psychiatric disorders. Some treatments for bedwetting include behavior modification, alarm devices, and medications.
Nocturnal Paroxysmal Dystonia (NPD)
This disorder is sometimes marked by seizure-like episodes during Non-REM sleep. Most evidence points to NPD being a form of epilepsy. Episodes of NPD typically recur several times per night.
Reviewed by The Sleep Medicine Center at The Cleveland Clinic.
Edited by Michael J. Breus, PhD, WebMD, September 2004.
Portions of this page © The Cleveland Clinic 2000-2005
Last Editorial Review: 6/20/2005