Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027497 (nausea)
 23,468 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This investigation explores the relationship between psychological factors and acute mountain sickness (AMS). AMS occurs in most people staying more than a few hours above 3500 m. Symptoms include headache, nausea, vomiting, insomnia, anorexia, etc. Subjects studied were climbers preparing for an expedition to the Himalayas (80 men and 20 women). The psychological investigation consisted in two mono-factorial tests: STAI (anxiety inventory) and Bortner stress scale. After the expedition, subjects were classified into two groups: those who were susceptible to AMS and those who were not. Results indicated that the two groups differed for trait-anxiety on one hand, and for the level of anxiety before the final ascent on the other hand. In both cases, subjects susceptible to AMS were significantly more anxious than those who were not.
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PMID:Control of anxiety and acute mountain sickness in Himalayan mountaineers. 148 85

Acetazolamide is a useful prophylactic for acute mountain sickness causing marked reduction in headache, nausea, vomiting, weakness, etc. Improvements correlate with increased arterial oxygen concentrations, reduction in proteinuria and peripheral oedema and other objective measures of acute mountain sickness. Evidence that Acetazolamide is beneficial for pulmonary oedema or cerebral oedema is scanty because of the lower frequency of these severe forms of mountain sickness. Dexamethasone, used prophylactically, also reduces the symptoms of acute mountain sickness partly due to its euphoric effect. Use of Acetazolamide as a treatment for established acute mountain sickness has been investigated. Large doses of Acetazolamide increase arterial oxygen levels over a few hours and this leads to a reduction of symptoms but data is limited and faster acting carbonic anhydrides inhibitors such as Methazolamide may be preferable in an emergency situation. There is no comparison of the effectiveness of Acetazolamide with other drugs used for treating acute mountain sickness such as steroids and calcium channel blocking drugs. Also, there is no data on drug combinations which could have additive effects and thereby be more beneficial than individual drugs.
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PMID:Acetazolamide and high altitude diseases. 148 96

Forty-seven climbers participated in a double-blind, randomized trial comparing acetazolamide 250 mg, dexamethasone 4 mg, and placebo every eight hours as prophylaxis for acute mountain sickness during rapid, active ascent of Mount Rainier (elevation 4,392 m). Forty-two subjects (89.4 percent) achieved the summit in an average of 34.5 hours after leaving sea level. At the summit or high point attained above base camp, the group taking dexamethasone reported less headache, tiredness, dizziness, nausea, clumsiness, and a greater sense of feeling refreshed (p less than or equal to 0.05). In addition, they reported fewer problems of runny nose and feeling cold, symptoms unrelated to acute mountain sickness. The acetazolamide group differed significantly (p less than or equal to 0.05) from other groups at low elevations (1,300 to 1,600 m), in that they experienced more feelings of nausea and tiredness, and they were less refreshed. These drug side effects probably obscured the previously established prophylactic effects of acetazolamide for acute mountain sickness. Separate analysis of an acetazolamide subgroup that did not experience side effects at low elevations revealed a prophylactic effect of acetazolamide similar in magnitude to the dexamethasone effect but lacking the euphoric effects of dexamethasone. This study demonstrates that prophylaxis with dexamethasone can reduce the symptoms associated with acute mountain sickness during active ascent and that acetazolamide can cause side effects that may limit its effectiveness as prophylaxis against the disease.
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PMID:A randomized trial of dexamethasone and acetazolamide for acute mountain sickness prophylaxis. 333 64

A self-completed questionnaire (modified Environmental Symptoms Questionnaire) was evaluated in a study of acute mountain sickness (AMS). The questionnaire scores for headache, nausea, and the general feeling of ill health correlated well with AMS scores obtained by clinical interview. Modifications in the instructions and the phrasing of some of the questions are suggested and we doubt whether factor analysis provides any better data than more simple statistical methods. The questionnaire is a useful additional method for the assessment of symptoms of AMS.
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PMID:The Environmental Symptoms Questionnaire in acute mountain sickness. 401 70

A double-blind randomized study of 45 climbers on Mt. Rainier was conducted to test the effectiveness of antacids in preventing acute mountain sickness. All 45 climbed to 3353 m, and 31 continued to the summit. Ten climbers listed acute mountain sickness as the reason for not attaining the summit. Of symptoms monitored throughout the climb, neither headache, nausea, dizziness, pounding heart, nor shortness of breath differed in severity between antacid-treated and placebo-treated groups. In both groups vital capacity decreased significantly with ascent (p less than 0.05), while peak flow (p less than 0.005) and minute ventilation (p less than 0.001) increased significantly. The 7 climbers with the most severe AMS symptom scores above 4000 m had significantly lower peak flow at sea level prior to ascent compared with the other 25 climbers who completed sea level tests (p less than 0.005). The results of this study fail to document efficacy for antacid use for the prevention of acute mountain sickness.
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PMID:Acute mountain sickness, antacids, and ventilation during rapid, active ascent of Mount Rainier. 634 73

Phenytoin sodium was evaluated for its effect on the development and intensity of acute mountain sickness (AMS) because of its ability to reduce intracellular Na+ concentrations in brain and thereby minimize any tendency to increase cellular volume, a hypothetical cause of AMS. Six men aged 19-35 were exposed to approximately 4600 m altitude in a hypobaric chamber for 52 h on two occasions separated by 10 d at sea level. Subjects received wither phenytoin or placebo for 18 h before (700 mg, divided dose) and throughout (100 mg t.i.d.) each altitude exposure in a double-blind, repeated-measures (crossover) design. Phenytoin serum concentrations ranged from 4.4-13.9 micrograms/ml during altitude exposure. Twice daily questionnaires and clinical evaluations showed no marked benefit from phenytoin on the occurrence, severity, or duration of AMS symptoms: headache, nausea, insomnia, and general malaise. Overall, 1 subject felt better, 2 felt worse, 1 felt the same; 2 were not suitably comparable. There was no observed relationship between serum levels and symptoms of AMS. Moderate degrees of weakness and dizziness were each reported by 3 subjects with phenytoin but not with placebo, however. Resting pulmonary ventilation, end-tidal PO2 and PCO2, map reading abilities and respiratory mask donning times were not affected by phenytoin. Under the conditions of this trial, phenytoin did not appear to be useful in managing AMS.
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PMID:Phenytoin: ineffective against acute mountain sickness. 676 69

Sixty-four climbers participated in a randomized clinical trial of acetazolamide prophylaxis for acute mountain sickness (AMS) during rapid, active ascent of MT Rainier. Twenty-nine (93.6%) of 31 climbers receiving acetazolamide and 25 (75.8%) of 33 receiving placebo attained the summit. Time spent ascending from sea level to the summit (4,394 m) averaged 33.5 hours (range, 23 to 48 hours). On the summit AMS was less common in climbers receiving acetazolamide, and they experienced less headache, nausea, drowsiness, shortness of breath, and dizziness and a greater sense of satisfaction and psychological well-being. Minute ventilation on the summit was significantly greater in subjects taking acetazolamide (24.9 +/- 2.0 L/min compared with 16.9 +/- 3.8 L/min). Expired vital capacity was also greater on the summit in the acetazolamide group (6.9 +/- 0.4 L compared with 5.8 +/- 0.4 L). We conclude that acetazolamide is effective in the prophylaxis of AMS for climbers attempting rapid, active ascent. Increased ventilation at altitude, producing an increased alveolar oxygen tension, may be related to the observed amelioration of symptoms.
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PMID:Acute mountain sickness and acetazolamide. Clinical efficacy and effect on ventilation. 704 33

The symptoms and signs of acute mountain sickness are present in about half of the tourists trekking in Nepal to an altitude of 42000 m. The most common symptoms are headache and nausea. Pulmonary rales are found in more than 10% of trekkers, while high altitude pulmonary edema is rare. Retinal hemorrhages occur almost exclusively above 5000 m. A careful history and physical examination are generally sufficient for medical evaluation of fitness for high altitude. There are no specific tests to predict performance at altitude. The most effective prophylaxis of acute mountain sickness is "slow" ascent, which is arbitrarily defined as an increase in sleeping altitude of 300-400 m per 24 hours. Sufficient fluid intake is also very important. Prophylactic administration of acetazolamide reduces the incidence and severity of acute mountain sickness. Mild forms of acute mountain sickness are treated by a rest day, whereas patients with severe disease should descend as soon as possible.
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PMID:[Incidence, prevention and therapy of acute mountain sickness]. 707 85

Acute altitude illnesses include acute mountain sickness (AMS), a benign condition involving headache, nausea, vomiting, irritability, insomnia, dizziness, lethargy, and peripheral edema, and potentially lethal high-altitude cerebral edema and pulmonary edema (HAPE). Recent evidence is summarized that AMS is related to cerebral edema secondary at least in part to hypoxic cerebral vasodilation and elevated cerebral capillary hydrostatic pressure. This results in reduced brain compliance with compression of intracranial structures in the absence of altered global brain metabolism. It is postulated that these primary intracranial events elevate peripheral sympathetic activity that acts neurogenically in the lung possibly in concert with pulmonary capillary stress failure to cause HAPE and in the kidney to promote salt and water retention. The adrenergic responses are likely modulated by striking increases of aldosterone, vasopressin and atrial natriuretic peptide. The effects of exercise on altitude-induced illness and various therapeutic regimens (acetazolamide, CO2 breathing, dexamethasone, and alpha adrenergic inhibitors) are discussed in light of this hypothesis.
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PMID:A neurogenic basis for acute altitude illness. 816 37

Headache, nausea, vomiting, insomnia and peripheral edema are the most important symptoms of acute mountain sickness (AMS), which occur within 6 to 12 h. after exposure to altitudes of more than 2500 m a. s. l. Usually, these symptoms resolve spontaneously; however, they may progress to life-threatening cerebral edema in some cases. High-altitude pulmonary edema (HAPE) is a noncardiogenic edema, which is often preceded by acute mountain sickness. Frequency and severity of these illnesses depend on the altitude, the rate of ascent and the degree of individual susceptibility. A low hypoxic ventilatory drive, sodium and water retention as well as increased capillary permeability are the most important pathophysiological factors which contribute to hypoxemia and edema formation in AMS. They are also important in the pathophysiology of HAPE. In addition, excessive hypoxic pulmonary artery hypertension is most likely crucial in the pathogenesis of HAPE. Constitutional factors which regulate ventilation and pulmonary artery pressure under hypoxia are considered the most important determinants of susceptibility to AMS and HAPE.
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PMID:[Clinical aspects and pathophysiology of altitude sickness]. 837 71


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