Orthostatic hypotension - wikipedia Orthostatic hypotension For the television science series, see Head Rush ( TV series ). Orthostatic hypotension Synonyms orthostasis, postural hypotension Pronunciation / ˌɔːrθəˈstætɪkˌhaɪpəˈtɛnʃən / Specialty Cardiology ( edit on Wikidata ) Orthostatic hypotension, also known as postural hypotension, occurs when a person 's blood pressure falls when suddenly standing up from a lying or sitting position. It is defined as a fall in systolic blood pressure of at least 20 mm Hg or diastolic blood pressure of at least 10 mm Hg when a person assumes a standing position. It occurs predominantly by delayed constriction of the lower body blood vessels, which is normally required to maintain an adequate blood pressure when changing position to standing. As a result, blood pools in the blood vessels of the legs for a longer period and less is returned to the heart, thereby leading to a reduced cardiac output. Mild orthostatic hypotension is common and can occur briefly in anyone, although it is prevalent in particular among the elderly and those with known low blood pressure. Severe drops in blood pressure can lead to fainting, with a possibility of injury. There are numerous possible causes for orthostatic hypotension, such as certain medications ( e.g. alpha blockers ), autonomic neuropathy, decreased blood volume, and age - related blood vessel stiffness. Apart from addressing the underlying cause, orthostatic hypotension may be treated with a recommendation to increase salt and water intake ( to increase the blood volume ), wearing compression stockings, and sometimes medication ( fludrocortisone, midodrine or others ). Contents 1 Signs and symptoms 2 Causes 2.1 Hypovolemia 2.2 Diseases 2.3 Medication 2.4 Other factors 3 Diagnosis 4 Management 4.1 Non-pharmacological management 4.2 Pharmacological management 5 Prognosis 6 See also 7 References 8 External links Signs and symptoms Orthostatic hypotension is characterised by symptoms that occur after standing ( from lying or sitting ), particularly when this is done rapidly. Many report lightheadedness ( a feeling that one might be about to faint ), sometimes severe. Generalized weakness or tiredness may also occur. Some also report difficulty concentrating, blurred vision, tremulousness, vertigo, anxiety, palpitations ( awareness of the heartbeat ), feeling sweaty or clammy, and sometimes nausea. A person may look pale. Causes Orthostatic hypotension is caused primarily by gravity - induced blood pooling in the lower extremities, which in turn compromises venous return, resulting in decreased cardiac output and subsequent lowering of arterial pressure. For example, changing from a lying position to standing loses about 700 ml of blood from the thorax, with a decrease in systolic and diastolic blood pressures. The overall effect is an insufficient blood perfusion in the upper part of the body. Still, the blood pressure does not normally fall very much, because it immediately triggers a vasoconstriction ( baroreceptor reflex ), pressing the blood up into the body again. ( Often, this mechanism is exaggerated and is why diastolic blood pressure is a bit higher when a person is standing up, compared to a person in the horizontal position. ) Therefore, a secondary factor that causes a greater than normal fall in blood pressure is often required. Such factors include low blood volume, diseases, and medications. Hypovolemia Orthostatic hypotension may be caused by low blood volume, resulting from bleeding, the excessive use of diuretics, vasodilators, or other types of drugs, dehydration, or prolonged bed rest ( immobility ) ; as well as occurring in people with anemia. Diseases The disorder may be associated with Addison 's disease, atherosclerosis ( build - up of fatty deposits in the arteries ), diabetes, pheochromocytoma, porphyria, and certain neurological disorders, including multiple system atrophy and other forms of dysautonomia. It is also associated with Ehlers -- Danlos syndrome and anorexia nervosa. It is also present in many patients with Parkinson 's disease resulting from sympathetic denervation of the heart or as a side - effect of dopaminomimetic therapy. This rarely leads to fainting unless the person has developed true autonomic failure or has an unrelated heart problem. Another disease, dopamine beta hydroxylase deficiency, also thought to be underdiagnosed, causes loss of sympathetic noradrenergic function and is characterized by a low or extremely low levels of norepinephrine, but an excess of dopamine. Quadriplegics and paraplegics also might experience these symptoms due to multiple systems ' inability to maintain a normal blood pressure and blood flow to the upper part of the body. Medication Tetrahydrocannabinol Orthostatic hypotension can be a side - effect of certain antidepressants, such as tricyclics or monoamine oxidase inhibitors ( MAOIs ). Marijuana and tetrahydrocannabinol can on occasion produce marked orthostatic hypotension. Orthostatic hypotension can also be a side effect of alpha - 1 blockers ( alpha adrenergic blocking agents ). Alpha blockers inhibit vasoconstriction normally initiated by the baroreceptor reflex upon postural change and the subsequent drop in pressure. Other factors Patients prone to orthostatic hypotension are the elderly, post partum mothers, and those having been on bedrest. People suffering from anorexia nervosa and bulimia nervosa often suffer from orthostatic hypotension as a common side - effect. Consuming alcohol may also lead to orthostatic hypotension due to its dehydrating effects. Diagnosis Orthostatic hypotension can be confirmed by measuring a person 's blood pressure after lying flat for 5 minutes, then 1 minute after standing, and 3 minutes after standing. Orthostatic hypotension is defined as a fall in systolic blood pressure of at least 20 mmHg and / or in the diastolic blood pressure of at least 10 mmHg between the supine reading and the upright reading. In addition, the heart rate should also be measured for both positions. A significant increase in heart rate from supine to standing may indicate a compensatory effort by the heart to maintain cardiac output or postural orthostatic tachycardia syndrome ( POTS ). A tilt table test may also be performed. Management Non-pharmacological management Apart from treating underlying reversible causes ( e.g., stopping or reducing certain medications ), there are a number of measures that can improve the symptoms of orthostatic hypotension and prevent episodes of syncope. Even small increases in the blood pressure may be sufficient to maintain blood flow to the brain on standing. In people who do not have a diagnosis of high blood pressure, drinking 2 -- 3 liters of fluid a day and taking 10 grams of salt can improve symptoms, by maximizing the amount of fluid in the bloodstream. Another strategy is keeping the head of the bed slightly elevated. This reduces the return of fluid from the limbs to the kidneys at night, thereby reducing nighttime urine production and maintaining fluid in the circulation. Various measures can be used to improve the return of blood to the heart : the wearing of compression stockings and exercises ( `` physical counterpressure manoeuvres '' or PCMs ) that can be undertaken just before standing up ( e.g., leg crossing and squatting ). Pharmacological management The medication midodrine can benefit people with orthostatic hypotension, The main side - effect is piloerection ( `` goose bumps '' ). Fludrocortisone is also used, although based on more limited evidence. A number of other measures have slight evidence to support their use indomethacin, fluoxetine, dopamine antagonists, metoclopramide, domperidone, monoamine oxidase inhibitors with tyramine ( can produce severe hypertension ), oxilofrine, potassium chloride, and yohimbine. Prognosis Orthostatic hypotension may cause accidental falls. It is also linked to an increased risk of cardiovascular disease, heart failure, and stroke. There is also observational data suggesting that orthostatic hypotension in middle age increases the risk of eventual dementia and reduced cognitive function. See also Orthostatic intolerance Orthostatic hypertension Postural orthostatic tachycardia syndrome Vasovagal response References Jump up ^ `` Orthostatic hypotension '' at Dorland 's Medical Dictionary Jump up ^ `` Orthostatic Hypotension Information Page National Institute of Neurological Disorders and Stroke ''. www.ninds.nih.gov. Retrieved 2017 - 03 - 26. Jump up ^ Kasper DL, Fauci AS, Hauser SL, Longo DL, James JL, Loscalzo J ( 2015 ). Harrison 's principles of internal medicine. 2 ( 19th ed. ). New York : McGraw - Hill Medical Publishing Division. p. 2639. ISBN 978 - 0 - 07 - 180215 - 4. Jump up ^ Idiopathic Orthostatic Hypotension and other Autonomic Failure Syndromes at eMedicine Jump up ^ `` What Causes Hypotension ? - NHLBI, NIH ''. www.nhlbi.nih.gov. Retrieved 27 March 2017. Jump up ^ Sim M, Hudon R. `` Acute intermittent porphyria associated with postural hypotension ''. Can Med Assoc J. 121 : 845 -- 6. PMC 1704473. PMID 497968. Jump up ^ `` Dopamine Beta - Hydroxylase Deficiency ''. GeneReviews -- NCBI Bookshelf. Jump up ^ Jiang W, Davidson JR ( 2005 ). `` Antidepressant therapy in patients with ischemic heart disease ''. Am Heart J. 150 ( 5 ) : 871 -- 81. PMID 16290952. doi : 10.1016 / j. ahj. 2005.01. 041. Jump up ^ Delini - Stula A, Baier D, Kohnen R, Laux G, Philipp M, Scholz HJ ( 1999 ). `` Undesirable blood pressure changes under naturalistic treatment with moclobemide, a reversible MAO - A inhibitor -- results of the drug utilization observation studies ''. Pharmacopsychiatry. 32 ( 2 ) : 61 -- 7. PMID 10333164. doi : 10.1055 / s - 2007 - 979193. Jump up ^ Jones RT. ( 2002 ). `` Cardiovascular system effects of marijuana ''. J Clin Pharmacol. 42 ( 11 Suppl ) : 58S -- 63S. PMID 12412837. doi : 10.1002 / j. 1552 - 4604.2002. tb06004. x. Jump up ^ Orthostatic Hypotension at Merck Manual of Diagnosis and Therapy Home Edition Jump up ^ `` STEADI - Measuring Orthostatic Blood Pressure '' ( PDF ). Centers for Disease Control and Prevention. Retrieved 20 December 2014. ^ Jump up to : Moya, A. ; Sutton, R. ; Ammirati, F. ; et al. ( 27 August 2009 ). `` Guidelines for the diagnosis and management of syncope ( version 2009 ) : The Task Force for the Diagnosis and Management of Syncope of the European Society of Cardiology ( ESC ) ''. European Heart Journal. 30 ( 21 ) : 2631 -- 2671. PMC 3295536. PMID 19713422. doi : 10.1093 / eurheartj / ehp298. CS1 maint : Explicit use of et al. ( link ) ^ Jump up to : Izcovich, A. ; Gonzalez Malla, C. ; Manzotti, M. ; Catalano, H.N. ; Guyatt, G. ( 22 August 2014 ). `` Midodrine for orthostatic hypotension and recurrent reflex syncope : A systematic review ''. Neurology. 83 ( 13 ) : 1170 -- 1177. PMID 25150287. doi : 10.1212 / WNL. 0000000000000815. Jump up ^ Logan, IC ; Witham, MD ( September 2012 ). `` Efficacy of treatments for orthostatic hypotension : a systematic review. ''. Age and ageing. 41 ( 5 ) : 587 -- 94. PMID 22591985. doi : 10.1093 / ageing / afs061. Jump up ^ Romero - Ortuno R, Cogan L, Foran T, Kenny RA, Fan CW ( 2011 ). `` Continuous noninvasive orthostatic blood pressure measurements and their relationship with orthostatic intolerance, falls, and frailty in older people ''. J Am Geriatr Soc. 59 ( 4 ) : 655 -- 65. PMID 21438868. doi : 10.1111 / j. 1532 - 5415.2011. 03352. x. Jump up ^ Ricci, F ; Fedorowski, A ; Radico, F ; Romanello, M ; Tatasciore, A ; Di Nicola, M ; Zimarino, M ; De Caterina, R ( 1 July 2015 ). `` Cardiovascular morbidity and mortality related to orthostatic hypotension : a meta - analysis of prospective observational studies. ''. European Heart Journal. 36 ( 25 ) : 1609 -- 17. PMID 25852216. doi : 10.1093 / eurheartj / ehv093. Jump up ^ Rawlings, Andreea ; et al. ( March 2017 ). Orthostatic Hypotension is Associated With 20 - year Cognitive Decline and Incident Dementia : the Atherosclerosis Risk in Communities ( ARIC ) Study ( PDF ). Epidemiology and Prevention / Lifestyle and Cardiometabolic Health 2017 Scientific Sessions. Portland, Oregon. CS1 maint : Explicit use of et al. ( link ) External links Classification V T D ICD - 10 : I95. 1 ICD - 9 - CM : 458.0 MeSH : D007024 DiseasesDB : 10470 Orthostatic hypotension at DMOZ Diseases of the autonomic nervous system ( G90, 337 ) HSAN II III / Familial dysautonomia IV / Congenital insensitivity to pain with anhidrosis V Orthostatic intolerance Postural orthostatic tachycardia syndrome Orthostatic hypotension Other Horner 's syndrome Multiple system atrophy Pure autonomic failure Autonomic dysreflexia Dysautonomia Autonomic neuropathy Cardiovascular disease ( vessels ) ( I70 -- I99, 440 -- 456 ) Arteries, arterioles and capillaries Inflammation Arteritis Aortitis Buerger 's disease Peripheral artery disease Arteriosclerosis Atherosclerosis Foam cell Fatty streak Atheroma Intermittent claudication Critical limb ischemia Monckeberg 's arteriosclerosis Arteriolosclerosis Hyaline Hyperplastic Cholesterol LDL Oxycholesterol Trans fat Stenosis Carotid artery stenosis Renal artery stenosis Other Aortoiliac occlusive disease Degos disease Erythromelalgia Fibromuscular dysplasia Raynaud 's phenomenon Aneurysm / dissection / pseudoaneurysm torso : Aortic aneurysm Abdominal aortic aneurysm Thoracic aortic aneurysm Aneurysm of sinus of Valsalva Aortic dissection Coronary artery aneurysm head / neck Intracranial aneurysm Intracranial berry aneurysm Carotid artery dissection Vertebral artery dissection Familial aortic dissection Vascular malformation Arteriovenous fistula Arteriovenous malformation Telangiectasia Hereditary hemorrhagic telangiectasia Vascular nevus Cherry hemangioma Halo nevus Spider angioma Veins Inflammation Phlebitis Venous thrombosis / Thrombophlebitis primarily lower limb Deep vein thrombosis abdomen Hepatic veno - occlusive disease Budd -- Chiari syndrome May -- Thurner syndrome Portal vein thrombosis Renal vein thrombosis upper limb / torso Mondor 's disease Paget -- Schroetter disease head Cerebral venous sinus thrombosis Post-thrombotic syndrome Varicose veins Gastric varices Portacaval anastomosis Caput medusae Esophageal varices Hemorrhoid Varicocele Other Chronic venous insufficiency Chronic cerebrospinal venous insufficiency Superior vena cava syndrome Inferior vena cava syndrome Venous ulcer Arteries or veins Angiopathy Macroangiopathy Microangiopathy Embolism Pulmonary embolism Cholesterol embolism Paradoxical embolism Thrombosis Vasculitis Blood pressure Hypertension Hypertensive heart disease Hypertensive emergency Hypertensive nephropathy Essential hypertension Secondary hypertension Renovascular hypertension Benign hypertension Pulmonary hypertension Systolic hypertension White coat hypertension Hypotension Orthostatic hypotension Retrieved from `` https://en.wikipedia.org/w/index.php?title=Orthostatic_hypotension&oldid=799409939 '' Categories : Vascular diseases Hypotension Peripheral nervous system disorders Hidden categories : CS1 maint : Explicit use of et al. All articles with unsourced statements Articles with unsourced statements from March 2017 Articles with unsourced statements from October 2016 Articles with unsourced statements from April 2015 Articles with DMOZ links Talk Contents About Wikipedia Deutsch Eesti Español Français 한국어 Bahasa Indonesia Italiano Македонски Nederlands 日本 語 Polski Português Русский Svenska 中文 Edit links This page was last edited on 7 September 2017, at 15 : 23. Text is available under the Creative Commons Attribution - ShareAlike License ; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia ® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization. About Wikipedia

Question: low blood pressure that occurs upon standing up is known
Answer: Orthostatic hypotension