No edit summary |
|||
| Line 4: | Line 4: | ||
ICD9 = {{ICD9|783.5}} | |
ICD9 = {{ICD9|783.5}} | |
||
}} |
}} |
||
| + | '''Polydipsia''' is a medical symptom in which the patient displays excessive [[thirst]].<ref name="pathophys">Porth, C. M. (1990). ''Pathophysiology: Concepts of altered health states''. Philadelphia: J.B. Lippincott Company.</ref> The word derives from the Greek ''πολυδιψία'', the feminine of ''πολυδίψιος'' (''polydipsios'', "very thirsty")<ref>[http://www.perseus.tufts.edu/cgi-bin/ptext?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3D%2384779 Polydipsios, Henry George Liddell, Robert Scott, ''A Greek-English Lexicon'', at Perseus]</ref> which is derived from ''πολύς'' (''polys'', "much, many") + ''δίψα'' (''dipsa'', "thirst"). An etymologically related term is [[dipsomaniac]], meaning an [[alcoholic]]. |
||
| − | '''Polydipsia''' is a medical term meaning abnormally large (''poly-'') intake of fluids by mouth. That is, [[drinking]] (''-dipsia''). The fluid is usually water, though some people may think of [[alcohol]] because of the etymologically-related term [[dipsomaniac]], meaning an [[alcoholic]]. |
||
| + | In animal experiments such noncontingent excessive drinking behavior can be shown to be maintained by operant [[schedules of reinforcement]] with food as a reinforcer. |
||
| − | Polydipsia is almost always associated with [[dehydration]] due to [[polyuria]] (excessive urination), if the condition is prolonged beyond a few hours in those with functioning kidneys. |
||
| + | ===Causes=== |
||
| − | It is often, and characteristically, found in [[diabetes mellitus|diabetics]], often as one of the initial symptoms, and in those who fail to take their anti-diabetic medications or whose dosages have become inadequate. It is also caused by other conditions featuring [[osmotic diuresis]] and by [[diabetes insipidus]] ("water diabetes"), and forms part of the differential diagnostic tree for them, as well. |
||
| + | This symptom is characteristically found in [[diabetes mellitus|diabetics]], often as one of the initial symptoms, and in those who fail to take their anti-diabetic medications or whose dosages have become inadequate. It can also be caused by a change in the [[osmolality]] of the [[extracellular fluid]]s of the body, [[hypokalemia]], decreased [[blood volume]] (as occurs during major [[hemorrhage]]), and other conditions that create a water deficit.<ref name="pathophys" /> This is usually a result of [[osmotic diuresis]] (increased urination), such as in [[diabetes insipidus]] ("tasteless" diabetes, as opposed to diabetes mellitus, "sweet" diabetes).<ref name="pathophys" /> Polydipsia is also a symptom of [[atropine]] or [[deadly nightshade|belladonna]] poisoning. |
||
| + | |||
| + | ===Polydipsia in Psychiatric Subsets=== |
||
| + | |||
| + | ''For the main article, see [[Psychogenic polydipsia]].'' |
||
| + | |||
| + | Psychogenic polydipsia is an excessive water intake<ref name="pathophys" /> seen in some patients with mental illnesses such as [[schizophrenia]], and/or the developmentally disabled. It should be taken very seriously, as the amount of water ingested exceeds the amount that can be excreted by the kidneys,<ref name="pathophys" /> and can on rare occasions be life-threatening as the body's [[Sodium#Biological_role|serum sodium]] level is diluted to an extent that seizures and cardiac arrest can occur. |
||
| + | |||
| + | While psychogenic polydipsia is generally not found outside the population of serious mental disorders, there is some anecdotal evidence of a milder form (typically called 'habit polydipsia' or 'habit drinking') that can be found in the absence of psychosis or other mental conditions. The excessive levels of fluid intake may result in a false diagnosis of [[diabetes insipidus]], since the chronic ingestion of excessive water can produce diagnostic results that closely mimic those of mild diabetes insipidus. |
||
| + | |||
| + | ===Diagnosis=== |
||
| + | Polydipsia is a symptom (evidence of a disease state), not a disease in itself. As it is often accompanied by [[polyuria]], investigations directed at diagnosing [[diabetes insipidus]] and [[diabetes mellitus]] can be useful. Blood serum tests can also provide useful information about the osmolality of the body's extracellular fluids. A decrease in osmolality caused by excess water intake will decrease the serum concentration of [[hematocrit|red blood cells]], [[blood urea nitrogen]] (BUN), and sodium.<ref name="pathophys" /> |
||
| − | ''[[Psychogenic polydipsia]]'' is a rare psychological disorder sometimes described in patients with mental illness or learning difficulty. If the patient is institutionalised, close monitoring by staff is necessary to control fluid intake. |
||
| − | Polydipsia is also a symptom of [[atropine]] or [[belladonna]] poisoning. |
||
==See also== |
==See also== |
||
| − | *[[ |
+ | * [[Adjunctive behavior]] |
| + | * [[Animal drinking behavior]] |
||
| + | * [[Human homeostasis]] |
||
| + | * [[Hyponatremia]] |
||
| + | * [[Polyphagia]] |
||
| + | * [[Water intoxication]] |
||
==References & Bibliography== |
==References & Bibliography== |
||
| + | {{reflist}} |
||
| − | |||
==Key texts== |
==Key texts== |
||
===Books=== |
===Books=== |
||
Latest revision as of 22:24, 14 January 2009
| [[Image:{{{Image}}}|190px|center|]] | |
|---|---|
| ICD-10 | R63.1 |
| ICD-O: | {{{ICDO}}} |
| ICD-9 | 783.5 |
| OMIM | {{{OMIM}}} |
| MedlinePlus | {{{MedlinePlus}}} |
| eMedicine | {{{eMedicineSubj}}}/{{{eMedicineTopic}}} |
| DiseasesDB | {{{DiseasesDB}}} |
Polydipsia is a medical symptom in which the patient displays excessive thirst.[1] The word derives from the Greek πολυδιψία, the feminine of πολυδίψιος (polydipsios, "very thirsty")[2] which is derived from πολύς (polys, "much, many") + δίψα (dipsa, "thirst"). An etymologically related term is dipsomaniac, meaning an alcoholic.
In animal experiments such noncontingent excessive drinking behavior can be shown to be maintained by operant schedules of reinforcement with food as a reinforcer.
Causes
This symptom is characteristically found in diabetics, often as one of the initial symptoms, and in those who fail to take their anti-diabetic medications or whose dosages have become inadequate. It can also be caused by a change in the osmolality of the extracellular fluids of the body, hypokalemia, decreased blood volume (as occurs during major hemorrhage), and other conditions that create a water deficit.[1] This is usually a result of osmotic diuresis (increased urination), such as in diabetes insipidus ("tasteless" diabetes, as opposed to diabetes mellitus, "sweet" diabetes).[1] Polydipsia is also a symptom of atropine or belladonna poisoning.
Polydipsia in Psychiatric Subsets
For the main article, see Psychogenic polydipsia.
Psychogenic polydipsia is an excessive water intake[1] seen in some patients with mental illnesses such as schizophrenia, and/or the developmentally disabled. It should be taken very seriously, as the amount of water ingested exceeds the amount that can be excreted by the kidneys,[1] and can on rare occasions be life-threatening as the body's serum sodium level is diluted to an extent that seizures and cardiac arrest can occur.
While psychogenic polydipsia is generally not found outside the population of serious mental disorders, there is some anecdotal evidence of a milder form (typically called 'habit polydipsia' or 'habit drinking') that can be found in the absence of psychosis or other mental conditions. The excessive levels of fluid intake may result in a false diagnosis of diabetes insipidus, since the chronic ingestion of excessive water can produce diagnostic results that closely mimic those of mild diabetes insipidus.
Diagnosis
Polydipsia is a symptom (evidence of a disease state), not a disease in itself. As it is often accompanied by polyuria, investigations directed at diagnosing diabetes insipidus and diabetes mellitus can be useful. Blood serum tests can also provide useful information about the osmolality of the body's extracellular fluids. A decrease in osmolality caused by excess water intake will decrease the serum concentration of red blood cells, blood urea nitrogen (BUN), and sodium.[1]
See also
- Adjunctive behavior
- Animal drinking behavior
- Human homeostasis
- Hyponatremia
- Polyphagia
- Water intoxication
References & Bibliography
Key texts
Books
Papers
Additional material
Books
Papers
External links
| This page uses Creative Commons Licensed content from Wikipedia (view authors). |