orthostatic intolerance

A condition (OMIM:604715) characterised by lightheadedness, fatigue, altered mentation, syncope and tachycardia upon assuming an upright position, and markedly elevated serum norepinephrine.

Molecular pathology
Defects in SLC6A2, which encodes a member of the sodium:neurotransmitter symporter that regulates norepinephrine homeostasis, are a cause of orthostatic intolerance.

or·tho·stat·ic in·tol·er·ance

(ōr'thō-stat'ik in-tol'ĕr-ăns)

Decreased venous return in the upright position typically experienced by astronauts after returning to an environment subject to gravity.

Medical Dictionary for the Health Professions and Nursing © Farlex 2012

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References in periodicals archive

Thus far, there are no valid tests to detect orthostatic intolerance leading to syncope among patients with MD.

Association between Syncope and Tumarkin Attacks in Meniere's Disease

Common syndromes of orthostatic intolerance. Pediatrics, 131(5), 968-980.

Increasing Functional Abilities of People with Postural Orthostatic Tachycardia Syndrome through Occupational Therapy

This can also result in problems from low blood pressure and heart rate control called orthostatic intolerance and POTS.

Effective Treatment of Pain and Sleep in Fibromyalgia--A Comprehensive Clinical Approach

They were healthy children without syncope, chest tightness, headache, or other symptoms of orthostatic intolerance, as demonstrated by a normal medical history, physical examination, and laboratory findings.

Increased Endogenous Sulfur Dioxide Involved in the Pathogenesis of Postural Tachycardia Syndrome in Children: A Case-Control Study

* Postexertional malaise * * Unrefreshing sleep * Plus at least one of the two following manifestations (chronic, severe): * Cognitive impairment * * Orthostatic intolerance Source: Institute of Medicine.

CDC Grand Rounds: chronic fatigue syndrome--advancing research and clinical education

Orthostatic intolerance. Symptoms have been shown to worsen with an upright posture according to objective measures such as orthostatic vital signs and head-up tilt testing, and symptoms improve with rest and leg elevation.

Clinical guidelines: Beyond myalgic encephalomyelitis / chronic fatigue syndrome--redefining an illness

In addition, patients should have cognitive impairment and/or experience orthostatic intolerance. The symptoms should persist for at least 6 months at a moderate, substantial, or severe intensity at least half of the time.

IOM: new name, criteria for chronic fatigue syndrome

Additionally, patients should have cognitive impairment and/or experience orthostatic intolerance. The symptoms should persist for at least 6 months at a moderate, substantial, or severe intensity at least half of the time.

IOM calls for new name for chronic fatigue syndrome

An Italian study on a volleyball player who had "acute psychosis" after high consumption of Red Bull, published in "The Journal of the Clinical Autonomic Research Society", concluded that "Considering the widespread of use of Red Bull among young who are often unaware of the drink's content, this case report suggests Red Bull be considered a possible cause of orthostatic intolerance." This means the abnormal and sudden increase in heartbeat rate.

Our kids' bodies contaminated with chemicals (Part 9)

Finally, Twisk suggests that cognitive deficits in ME/CFS can be explained by neurological abnormalities and changes in brain structure and function [2], including orthostatic intolerance and a reduction in gray matter volume, among others.

Rebuttal to Ickmans et al. Association between cognitive performance, physical fitness, and physical activity level in women with chronic fatigue syndrome