Hyperreflexia is overactive or overresponsive bodily

reflexes In biology, a reflex, or reflex action, is an involuntary, unplanned sequence or action and nearly instantaneous response to a stimulus. Reflexes are found with varying levels of complexity in organisms with a nervous system. A reflex occurs ...

. Examples of this include twitching and spastic tendencies, which indicate upper disease of the upper motor neurons and the lessening or loss of control ordinarily exerted by higher

brain A brain is an organ (biology), organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as Visual perception, vision. I ...

centers of lower neural pathways (disinhibition). The most common cause of hyperreflexia is spinal-cord injury (''see'' "

Autonomic dysreflexia Autonomic dysreflexia (AD) is a potential medical emergency classically characterized by uncontrolled hypertension and bradycardia, although tachycardia is known to commonly occur. AD occurs most often in individuals with spinal cord injuries wit ...

"). Standard stimuli, such as the filling of the bladder, can cause excessive responses from the nervous system; the causes are not known. Hyperreflexia also has many other causes, including the side effects of drugs and stimulants;

hyperthyroidism Hyperthyroidism is the condition that occurs due to excessive production of thyroid hormones by the thyroid gland. Thyrotoxicosis is the condition that occurs due to excessive thyroid hormone of any cause and therefore includes hyperthyroidis ...

;

electrolyte An electrolyte is a medium containing ions that is electrically conducting through the movement of those ions, but not conducting electrons. This includes most soluble salts, acids, and bases dissolved in a polar solvent, such as water. Upon ...

imbalance;

serotonin syndrome Serotonin syndrome (SS) is a group of symptoms that may occur with the use of certain serotonergic medications or drugs. The degree of symptoms can range from mild to severe, including a potentiality of death. Symptoms in mild cases include high ...

; severe brain trauma;

multiple sclerosis Multiple (cerebral) sclerosis (MS), also known as encephalomyelitis disseminata or disseminated sclerosis, is the most common demyelinating disease, in which the insulating covers of nerve cells in the brain and spinal cord are damaged. This ...

;

Reye syndrome Reye syndrome is a rapidly worsening brain disease. Symptoms of Reye syndrome may include vomiting, personality changes, confusion, seizures, and loss of consciousness. While liver toxicity typically occurs in the syndrome, jaundice usually doe ...

; and

preeclampsia Pre-eclampsia is a disorder of pregnancy characterized by the onset of high blood pressure and often a significant amount of protein in the urine. When it arises, the condition begins after 20 weeks of pregnancy. In severe cases of the disease ...

. Treatment depends on the cause of the hyperreflexia. If drugs cause it, treatment may require that they not be used. Recovery from hyperreflexia can occur several hours to several months after a spinal-cord injury; the phase of recovery is likely to occur in stages rather than on a continuum.Little, J., Ditunno, J. F., Stien, S., A., Harris, R. M. (1999). "Incomplete spinal cord injury: Neuronal mechanisms of motor recovery and hyperreflexia. ''Archives of Physical Medicine and Rehabilitation'' 80 (5): 587-599. The late stage is between two weeks and several months. Patients with a severe spinal-cord injury (SCI) mainly present with a later stage of recovery because during the early stages they present with spinal shock. Reflex and motor recovery can sometimes occur simultaneously.

References

External links

NIH/Medline
*
''Archives of Physical Medicine and Rehabilitation''
{{Nervous and musculoskeletal system symptoms and signs Symptoms and signs: Nervous system

See also

References

External links