View source for Oral rehydration therapy

[[File:Cholera rehydration nurses.jpg|right|thumb|250px|Nurses encouraging a patient to drink an oral rehydration solution to combat dehydration caused by cholera.]]

'''Oral Rehydration Therapy''' ('''ORT''') is a simple treatment for [[dehydration]] associated with [[diarrhea]], particularly [[gastroenteritis]] or gastroenteropathy, such as that caused by [[cholera]] or [[rotavirus]]. ORT consists of a [[solution]] of [[salt]]s and [[sugars]] that is taken [[Route of administration#Enteral|by mouth]]. It is used around the world, but is most important in the [[developing country|developing world]], where it saves millions of children a year from death due to [[diarrhea]], the second leading cause of death (after [[pneumonia]]) in children under five.<ref name=unicef_sowc>{{cite book | title=The State of the World's Children 2008: Child Survival | url=http://www.unicef.org/sowc08/docs/sowc08.pdf | author=[[UNICEF]] | publisher = United Nations Children's Fund | date = December 2007 | isbn=978-92-806-4191-2 | page=8 }}</ref>

== History ==
Prescriptions from the ancient Indian physician [[Sushruta]] date back over 2500 years with treatment of acute diarrhea with [[rice]] water, [[coconut water|coconut juice]], and [[carrot]] soup. However, this knowledge did not carry over to the Western world, as dehydration was found to be the major cause of death secondary to the 1829 [[cholera]] pandemic in Russia and Western Europe. In 1831, [[William Brooke O'Shaughnessy]] noted the loss of water and salt in the stool of cholera patients and prescribed [[Intravenous therapy|intravenous fluid therapy]] (IV) to compensate. The results were remarkable, as patients who were on the brink of death from dehydration recovered. The mortality rate of cholera dropped from 70&nbsp;percent to 40&nbsp;percent with the use of [[Tonicity#Hypertonicity|hypertonic]] IV solutions.<ref name=guerrant_ort_history>{{cite journal | last1 = Guerrant | first1 = RL | last2 = Carneiro-Filho | first2 = BA | last3 = Dillingham | first3 = RA | year=2003 | month=August | title=Cholera, Diarrhea, and Oral Rehydration Therapy: Triumph and Indictment | journal=Clinical Infectious Diseases | volume=37 | issue=3 | pages=398–405 | pmid=12884165 |url=http://cid.oxfordjournals.org/content/37/3/398.full.pdf | doi=10.1086/376619|accessdate=2008-07-15 }}</ref> IV fluid replacement became entrenched as the standard of care for moderate/severe dehydration for over a hundred years. ORT replaced it with the support of several independent key advocates that ultimately convinced the medical community of the efficacy of ORT.<ref name=ruxin />

In the late 1950s, ORT was prescribed by [[Hemendra Nath Chatterjee|Dr. Hemendra Nath Chatterjee]] in India for cholera patients.<ref name=chatterjee>{{cite journal| last= Chatterjee| first = HN | journal = Postgraduate Medical Journal | year = 1957| volume = 33|issue = 380| pages=278–84| title=Reduction of Cholera Mortality by the Control of Bowel Symptoms and Other Complications|pmc=2501333| doi= 10.1136/pgmj.33.380.278| pmid= 13431557}}</ref> Although his findings predate physiological studies, his results failed to gain credibility and recognition because they did not provide [[scientific control]]s and detailed analysis.<ref name=ruxin>{{cite journal | last1 = Ruxin | first1 = JN | title = Magic bullet: the history of oral rehydration therapy | journal = Medical History | year = 1994 | volume = 38 | pages = 363–97 | pmc=1036912 | pmid = 7808099 | issue = 4 }}</ref> Credit for discovery that in the presence of glucose, sodium and chloride became absorbable during diarrhea (in cholera patients) is typically ascribed to Dr. Robert A. Phillips. However, early attempts to translate this observation into an effective oral rehydration solution failed, due to incorrect solution formula and inadequate methodology.<ref name=ruxin/>

In the early 1960s, biochemist [[Robert K. Crane]] discovered the sodium-glucose [[Co-transport|cotransport]] as the mechanism for intestinal glucose absorption.<ref>Robert K. Crane, D. Miller and I. Bihler. "The restrictions on possible mechanisms of intestinal transport of sugars". In: Membrane Transport and Metabolism. Proceedings of a Symposium held in Prague, August 22–27, 1960. Edited by A. Kleinzeller and A. Kotyk. [[Academy of Sciences of the Czech Republic|Czech Academy of Sciences]], Prague, 1961, pp. 439–449.</ref> Around the same time, others showed that the intestinal mucosa was not disrupted in cholera, as previously thought. These findings were confirmed in [[human experiments]], where it was first shown that a glucose-saline oral therapy solution administered in quantities matching measured diarrhea volumes was effective in significantly decreasing the necessity for IV fluids by 80&nbsp;percent.<ref name=nalin_first_ort_successful_trial>{{cite journal | last=Nalin |first=David R |coauthors= Richard A. Cash; Rafiqul islam; Majid Molla; Robert A.Phillips|year=1968|month=August|title=Oral Maintenance Therapy for cholera in Adults|journal=The Lancet|volume=2|pages=370–2 | doi=10.1016/S0140-6736(68)90591-6 | issue=7564 }}</ref> These results helped establish the physiological basis for the use of ORT in [[clinical medicine]].<ref name=guerrant_ort_history />

The events surrounding the [[Bangladesh Liberation War]] in 1971 convinced the world of the effectiveness of ORT.<ref name=ruxin/> As medical teams ran out of intravenous fluids to treat the spreading cholera epidemic, Dr. [[Dilip Mahalanabis]] instructed his staff to distribute oral rehydration salts (ORS) to the 350,000 people in refugee camps. Over 3,000 patients with cholera were treated, and the [[mortality rate|death rate]] was only 3.6&nbsp;percent, compared with the typical 30&nbsp;percent seen in intravenous fluid therapy.<ref name=guerrant_ort_history /> The fact that ORT was delivered primarily by family members instead of trained staff across such a large population in an emergency fashion was demonstrative proof of the utility of ORT against cholera.<ref name=ruxin/>

Between 1980 and 2006, ORT decreased the number of worldwide deaths from 5 million a year to 3 million a year.<ref name=gerlin>{{cite journal |last=Gerline|first=Andrea |magazine=Time Magazine |title=A Simple Solution| url=http://www.time.com/time/printout/0,8816,1543876,00.html|date=October 8, 2006}}</ref> Death from diarrhea was the leading cause of infant mortality in the developing world until ORT was introduced.<ref name=lancet78/> It is now the second leading cause of mortality for children under five, accounting for 17&nbsp;percent of all deaths, second only to [[pneumonia]], at 19&nbsp;percent.<ref name=unicef_sowc/> Its remarkable success has led to naming the discovery of its underlying physiological basis as "potentially the most important medical advance [of the 20th]&nbsp;century."<ref name=lancet78>{{cite journal| title=Water with Sugar and Salt| journal = The Lancet | year = 1978 | month = August |doi=10.1016/S0140-6736(78)91698-7| volume=312| issue=8084| pages=300–1 }}</ref> ORT is part of UNICEF's GOBI program, a low cost program to increase child survival in developing countries, including growth monitoring, ORT, breastfeeding, and immunization.<ref>{{cite book | title= 1946-2006 Sixty Years for Children |url= http://www.unicef.org/publications/files/1946-2006_Sixty_Years_for_Children.pdf | year= 2006 | month= November | format= pdf | publisher= [[UNICEF]] |isbn=92-806-4053-4 |accessdate= 2008-06-07 | author= [[UNICEF]] }}</ref> Despite the success and effectiveness of ORT, its uptake has recently slowed and even reversed in some developing countries. This raises concerns for increased mortality from diarrhea and highlights the need for effective community-level behavioral change and global funding and policy.<ref name=ram>{{cite journal |last = Ram|first=Pavani Kalluri |coauthors=Misun Choi; Lauren S Blum; Annah W Wamae; Eric D Mintz; Alfred V Bartlett|title=Declines in case management of diarrhoea among children less than five years old| journal=Bulletin of the World Health Organization| year= 2008 |pages = 240–240 |volume=86 |issue=3 |url= http://www.who.int/bulletin/volumes/86/3/07-041384/en/index.html |doi=10.2471/BLT.07.041384 |pmc = 2647400 |accessdate=2009-02-16 |pmid=18368194}}</ref>

The individuals and organizations involved in the development of ORT have been recognized widely. The 2001 Gates Award for Global Health was awarded to the [[International Centre for Diarrhoeal Disease Research|Centre for Health and Population Research]], located in [[Dhaka]], Bangladesh, for its role in the development of ORT.<ref name=gates01>{{cite web|author = [[Bill & Melinda Gates Foundation]]| url=http://www.gatesfoundation.org/gates-award-global-health/Pages/2001-centre-for-health-and-population-research.aspx|title = Centre for Health and Population Research - 2001 Gates Award for Global Health Recipient |accessdate = 2009-02-21}}</ref> In 2002, the first [[Pollin Prize for Pediatric Research]] was awarded to Dr. Norbert Hirschhorn, Dr. [[Dilip Mahalanabis]], Dr. [[David Nalin]], and Dr. Nathaniel F. Pierce for their contributions in the discovery and implementation of ORT.<ref name=pollin02>{{cite web|author = [[NewYork-Presbyterian Hospital]] | title = First Pollin Prize in Pediatric Research Recognizing Developers of Revolutionary Oral Rehydration Therapy |url=http://nyp.org/news/hospital/2002-pollin-prize.html|accessdate=2009-02-22}}</ref> For promoting the use of ORT, the 2006 [[Prince Mahidol Award]] was awarded to Dr. [[Richard A. Cash]] of [[Harvard School of Public Health]], Dr. [[David Nalin]], and Dr. [[Dilip Mahalanabis]] in the field of public health; and to Dr. Stanley G Schultz in the field of medicine.<ref name=mahidol06>{{cite web|author = [http://www.princemahidolaward.org/index.en.php Prince Mahidol Award Foundation] | title=Prince Mahidol Award 2006| url = http://www.princemahidolaward.org/publications/PMA_Program06.pdf|format = pdf|accessdate=2009-02-22}}</ref>

==Availability==
The World Health Organizations states that some home products can be used to treat and prevent dehydration. This includes salted rice water, salted yogurt drink, and salted vegetable or chicken soup. A home-made solution of one liter of plain water with 3 grams table salt (one level teaspoonful) and 18 grams common sugar (three tablespoons) can also be made. And a medium amount of salt can also be added to water in which cereal has been cooked, unsalted soup, green coconut water, unsweetened weak tea, and unsweetened fruit juice. <ref name=WHOtreatmentdiarrhoea2005/>  The homemade solution should have the "taste of tears."<ref name=2010WorldCupTravellersGuide>[http://www.who.int/topics/test/food_safety/safe_food_travel.pdf A GUIDE ON SAFE FOOD FOR TRAVELLERS], WELCOME TO SOUTH AFRICA, HOST TO THE 2010 FIFA WORLD CUP (bottom left of page 1).</ref>  If available, supplemental zinc and potassium can be added to or given with the homemade solution.<ref name=WHOtreatmentdiarrhoea2005/>

ORT is available anywhere that adequate nutrition is available. ORS, on the other hand, is typically packaged in pre-measured sachets that are ready to be mixed in with water (generally 1[[liter|L]]). These are available via commercial manufacturers<ref name=rehydrate_suppliers>{{cite web|title = Worldwide Suppliers of ORS - rehydrate.org|url = http://rehydrate.org/resources/suppliers.htm|accessdate = 2009-02-19}}</ref> or supplied by local/regional governments or relief agencies such as [[UNICEF]]. In 1996, UNICEF distributed 500 million sachets of ORS to over 60 developing nations.<ref name=unicef96_childrenstate_ors>{{cite web|author=[[UNICEF]]|title=The State of the World's Children 1996|year = 1996|url = http://www.unicef.org/sowc96/joral.htm|accessdate = 2009-02-19}}</ref> Commercial suppliers produce a variety of formulations, and there is no restriction as to what formulation can be marketed as ORS. As such, some vendors include extra sugar or other flavoring to make the product more palatable, popular examples in the US being the various flavors and formulations of Drip Drop ORS and [[Pedialyte]].

Scheduled to start in October 2011,{{update after|2011|10}} there is a pilot program in Zambia to piggyback onto Coca-Cola distribution channels using the empty spaces in cases to include [[Colalife]], which are wedge-shaped packets of medicines including oral rehydration salts.<ref>[http://www.timescolonist.com/business/Coke+supply+chain+could+distribute+needy/5490655/story.html Coke's supply chain could distribute aid to the needy], Marc And Craig Kielburger, Times Colonist, [Victoria & Vancouver Island, Canada], October 2, 2011.</ref>

==Definition==

The definition of ORT has changed over time, broadening in scope and encompassing a definition of a specific therapy appropriate for rehydration. Initially, in the early 1980s, ORT was defined only as the solution prescribed by the [[WHO]]/[[UNICEF]]. It was later changed in 1988 to encompass recommended home fluids, because the official preparation was not always readily available. It was amended once again in 1988 to include continued feeding as appropriate management. In 1991, the definition was changed to define ORT as any increase in administered fluids. The final change came in 1993, and is the definition used today, which states that ORT is an increase in administered fluids and continued feeding.<ref name=who_bu0747 />

===Basic solution===
Where ORS sachets are not available, home-prepared solutions are typically used. While many different recipes exist to increase palatability (e.g. adding flavor, citrus, savory, etc.), all are based on a standard ratio of water, sugar, and salt.

A basic oral rehydration therapy solution is composed of:<ref>World Health Organization, Global Task Force on Cholera Control, [http://www.who.int/cholera/technical/en/ WHO position paper on Oral Rehydration Salts to reduce mortality from cholera]</ref><ref name=wikihow_ors>{{cite web | title=How to Make an Oral Rehydration Salts Drink (ORS) | url = http://www.wikihow.com/Make-an-Oral-Rehydration-Salts-Drink-(ORS) | accessdate = 2011-02-26}}</ref>

* 30 ml (6 level tsp) of sugar
* 2.5 ml (1/2 level tsp) of salt, dissolved into
* 1 litre (4.25 Cups) of clean water

Note that these expedient rehydration mixtures do not replenish potassium, and usage over long term may result in [[hypokalemia]]. To obtain some potassium, 125 ml (4 fl oz) of orange juice or some mashed banana can be added to the mixture.<ref name=rehydrate_homemade>{{cite web | title=ORS Made at Home - rehydrate.org| url = http://rehydrate.org/solutions/homemade.htm|accessdate = 2009-02-19}}</ref>

===WHO/UNICEF definition of ORS===
{| class="wikitable" align=right border="1" style="margin: 1em auto 1em auto; text-align:center;"
|+ Concentrations of ingredients in reduced osmolarity ORS<ref name = unicef_reducedORS />
! Ingredient || [[Gram (unit)|g]]/[[Liter|L]] || m[[Mole (unit)|mol]]/[[Liter|L]]
|-
|align=left| [[sodium chloride]] (NaCl) || 2.6 || 45
|-
|align=left| [[glucose]], anhydrous (C<sub>6</sub>H<sub>12</sub>O<sub>6</sub>)  || 13.5 || 75
|-
|align=left| [[potassium chloride]] (KCl) || 1.5 || 20
|-
|align=left| [[trisodium citrate]], dihydrate<br/>Na<sub>3</sub>C<sub>6</sub>H<sub>5</sub>O<sub>7</sub>·2H<sub>2</sub>O || 2.9 || 10
|-
!colspan=2| Dissociates into || mmol/L
|-
|colspan=2| [[sodium]]    || 75
|-
|colspan=2| [[potassium]] || 20
|-
|colspan=2| [[chloride]]  || 65
|-
|colspan=2| [[glucose]]   || 75
|-
|colspan=2| [[citrate]]   || 10
|-
|colspan=2| TOTAL         || 245
|}

The [[WHO]] and [[UNICEF]] jointly maintain the official guidelines<ref name=who_ort>{{cite web|author=[[WHO]] |title = Pharmacopoeia Library: Oral Rehydration Salts|url=http://www.who.int/phint/en/p/docf/|accessdate=2009-02-16}}</ref> for the contents of reduced [[osmolarity]] ORS packets. These guidelines are used by manufacturers of commercial ORS packets that are available for purchase and were last updated in 2006.<ref name=unicef_ort_update>{{cite web|author=[[UNICEF]] |title=Improved formula for oral rehydration salts to save children's lives|url=http://www.unicef.org/media/media_31825.html|accessdate=2008-07-15}}</ref> The reduced osmolarity ORS has a total osmolarity of 245 m[[Mole (unit)|mol]]/[[Liter|L]].<ref name=unicef_reducedORS />

=== Switch to reduced osmolarity ORS ===

In 2003, WHO/UNICEF changed the ORS formula to a reduced osmolarity version from what it had been recommending for over two decades prior.<ref name=unicef_reducedORS>{{cite web|title = UNICEF: New formulation of Oral Rehydration Salts (ORS) with reduced osmolarity|url = http://www.supply.unicef.dk/catalogue/bulletin9.htm|accessdate = 2009-02-16}}</ref> This change was in response to numerous studies that showed that the standard ORS formula was ineffective in reducing diarrheal stool output compared to other solutions, including rice water.<ref name=wong1>{{cite journal | last = Wong | first = HB | title=Rice water in treatment of infantile gastroenteritis | journal = The Lancet | year = 1981 | volume = 318 | issue = 8237 | pages = 102–3 | pmid = 6113434 | doi = 10.1016/S0140-6736(81)90462-1 }}</ref><ref name=wong2>{{cite journal |last=Wong|first=HB|title=Gastroenteritis: III. Rice-water in the management of infantile gastroenteritis in Singapore |journal = Journal of Singapore Paediatric Society|year= 1981|volume=23|issue=3–4|pages=113–7|pmid = 7052847 }}</ref><ref name=mehta>{{cite journal | last = Mehta |first =MN|coauthors=Subramaniam S | title =Comparison of rice water, rice electrolyte solution, and glucose electrolyte solution in the management of infantile diarrhoea | journal = The Lancet | year = 1986 | volume=327 | issue=8485 | pages = 843–5 | pmid= 2870323 | doi = 10.1016/S0140-6736(86)90948-7 }}</ref><ref name=molina>{{cite journal |author = Molina S|coauthors = Vettorazzi C; Peerson JM; Solomons NW; Brown KH|title =Clinical trial of glucose-oral rehydration solution (ORS), rice dextrin-ORS, and rice flour-ORS for the management of children with acute diarrhea and mild or moderate dehydration|journal = Pediatrics | year = 1995|volum = 95|issue = 2|pages = 191–197|pmid = 7838634 |volume = 95 }}</ref><ref name=bhattacharya>{{cite journal | author = Bhattacharya SK|coauthors = Dutta P; Dutta D; Chakraborti MK|title=Super ORS|journal = Indian Journal of Public Health|year = 1990|volume = 34|issue = 1|pages = 35–7|pmid = 2101384}}</ref> Additionally, further studies showed that a reduced osmolarity solution not only decreased stool output, but also resulted in less vomiting and fewer unscheduled intravenous therapy cases.<ref name=santosham>{{cite journal | last1 = Santosham | first1 = M | last2 = Fayad | first2 = I | last3 = Zikri | first3 = M | last4 = Hussein | first4 = A | last5 = Amponsah | first5 = A | last6 = Duggan | first6 = C | last7 = Hashem | first7 = M | last8 = Sady | first8 = N | last9 = Zikri | first9 = M | title = A double-blind clinical trial comparing World Health Organization oral rehydration solution with a reduced osmolarity solution containing equal amounts of sodium and glucose |journal = The Journal of Pediatrics|year = 1996 | month = January |volume = 128|issue = 1|pages = 45–51|pmid = 8551420 | doi =10.1016/S0022-3476(96)70426-2 }}</ref><ref name=Kim>{{cite journal | last1 = Hahn | first1 = S | last2 = Kim | first2 = Y | last3 = Garner | first3 = P | journal = Cochrane Database of Systematic Reviews | year = 2002 | id= CD002847 | pmid = 11406049 | doi=10.1002/14651858.CD002847 | url = http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD002847/pdf | accessdate = 2009-02-16 | title = Reduced osmolarity oral rehydration solution for treating dehydration caused by acute diarrhoea in children | issue = 1 | editor1-last = Hahn | editor1-first = Seokyung | pages = CD002847  }}</ref><ref name = choicestudy>{{cite journal | author = CHOICE Study Group | title = Multicenter, randomized, double-blind clinical trial to evaluate the efficacy and safety of a reduced osmolarity oral rehydration salts solution in children with acute watery diarrhea | journal = Pediatrics | year = 2001 | month = April | volume = 107 | issue = 4 | pages = 613–8 | pmid = 11335732 | doi = 10.1542/peds.107.4.613 }}</ref> Although UNICEF certifies reduced osmolarity ORS for all forms of dehydration,<ref name=unicef_reducedORS /> at least one study cautions that for high stool output cholera-based diarrhea, reduced osmolarity ORS may not sufficiently replenish electrolyte levels, leading to [[hyponatremia]]. Though the actual consequence of this appeared negligible, further study was recommended.<ref name = murphy>{{cite journal| last1 = Murphy | first1 = CK | last2 = Hahn | first2 = S | last3 = Volmink | first3 = J | title = Reduced osmolarity oral rehydration solution for treating cholera | journal = Cochrane Database of Systematic Reviews | year = 2004 | id = CD003754 | pmid=15495063 | doi = 10.1002/14651858.CD003754.pub2 | issue = 4| editor1-last = Murphy| editor1-first = Colleen K| pages = CD003754 }}</ref><ref name="pmid22161381">{{cite journal | last1 = Musekiwa | first1 = A | last2 = Volmink | first2 = J | title = Oral rehydration salt solution for treating cholera: ≤ 270 mOsm/L solutions vs ≥ 310 mOsm/L solutions | journal = Cochrane Database of Systematic Reviews | issue = 12 | id = CD003754 | year = 2011 | pmid = 22161381 | doi = 10.1002/14651858.CD003754.pub3 | editor1-last = Musekiwa | editor1-first = Alfred | volume = 12 | pages = CD003754 }}</ref>

The change reduced the osmolarity of the ORS from 311 m[[Mole (unit)|mol]]/[[Liter|L]] to 245&nbsp;mmol/L. The ingredients reduced in concentration were [[glucose]] and [[sodium chloride]]. [[Potassium]] and [[citrate]] concentrations remained the same.<ref name=unicef_reducedORS/> The benefits of the reduced osmolarity ORS are reducing stool volume by about 25&nbsp;percent, reducing vomiting by nearly 30&nbsp;percent,<ref name=unicef_reducedORS_faq>{{cite web|author = [[UNICEF]] |title="New ORS" Q&A|url = http://www.supply.unicef.dk/catalogue/NewORSQ&A.pdf|accessdate = 2009-02-16}}</ref> and reducing the need for unscheduled intravenous therapy by 33&nbsp;percent.<ref name=who_manual />

Many Indian pharmacy manufacturers lobbied to oppose this change as the reduction in [[glucose]] and [[sodium chloride]] concentrations degraded the taste of the ORS solution and hence adversely affected their sales. Dr Dinesh Kumar Tiwari lead a decade long campaign against the old high osmolarity formula, he called "Sweet Killer". The recommendations were at last adopted by [http://www.cdsco.nic.in CDSCO].

== Administration ==
{{howto|section|date=August 2011}}
[[File:Ors sachet pour.png|thumb|right|Pouring of an ORS [[sachet]] into a bottle]]

Current WHO/UNICEF guidelines,<ref name=who_unicef_ors>{{cite web|title = Oral Rehydration Salts: Production of the new ORS | author = [[WHO]], [[UNICEF]]| url = http://libdoc.who.int/hq/2006/WHO_FCH_CAH_06.1.pdf|format = pdf|accessdate = 2009-02-16}}</ref> recommend that ORT should begin at home with "home fluids" or a home-prepared "sugar and salt" solution at the first sign of diarrhea to prevent dehydration.<ref name=who_cdd_93.44>{{cite web|title = WHO/CDD/93.44: The selection of fluids and food for home therapy to prevent dehydration from diarrhoea: Guidelines for developing a national policy|author = [[WHO]]: Programme for the Control of Diarrhoeal Diseases|url = http://whqlibdoc.who.int/hq/1993/WHO_CDD_93.44.pdf|accessdate = 2009-02-16}}</ref> Feeding should be continued at all times.<ref name=who_bu0747>{{cite journal|author=Cesar G. Victora | coauthors=Jennifer Bryce, Olivier Fontaine, & Roeland Monasch| title = Reducing deaths from diarrhoea through oral rehydration therapy | journal = Bulletin of the World Health Organization| year = 2000| volume = 78| issue = 10| pages=1246–55|url=http://www.who.int/entity/bulletin/archives/78(10)1246.pdf| publisher = [[WHO]]|id=00-0747|pmid= 11100619 |accessdate = 2009-02-17|pmc=2560623}}</ref> After initial fluid volume has been restored, the regimen should be switched to official preparations of ''oral rehydration salts'' (ORS) at the appropriate dosing times to maintain adequate hydration and proper electrolyte balance.

During the home-prepared stage, care should be taken to select the proper type of fluid to administer. The fluids given must contain both sugar and salt in the proper amounts. Liquids without salt can lead to low body salt ([[hyponatremia]]) because the diarrheal stool contains salt that must be replenished. Additionally, sugar must also be present in the administered fluid because salt absorption is coupled with sugar in the intestine via the [[SGLT1]] transporter.<ref name=who_cdd_93.44 />

Appropriate drinks to administer during the home-prepared stage include official ORSs, salted [[rice water]], salted yogurt-based drinks, and vegetable or chicken soup with salt. [[Clean water]] should always be used when preparing a solution. Drinks to be avoided include soft drinks, sweetened fruit drinks, sweetened tea, coffee, and medical tea infusions with diuretic effects due to high sugar content and/or caffeine. In addition, drinks with a high concentration ([[osmolarity]]) of sugar can worsen diarrhea as they draw water out of the body and into the intestine because of their [[hypertonic]]ity.<ref name=who_cdd_93.44 />

If dehydration ensues even when ORT is begun with a home-prepared solution, if available, a qualified health professional should manage further rehydration with ORS to ensure proper [[electrolyte]] balance and to facilitate rapid rehydration, and treatment of the underlying cause of dehydration if appropriate.<ref name=who_manual />

===Food and supplements===
An adult or child with diarrhea should continue to eat, and infants should continue to breast-feed.<ref name=WHOtreatmentdiarrhoea2005/><ref>[http://www.cdc.gov/haiticholera/pdf/chw_trainingmaterialsforcholera.pdf Community Health Worker Training Materials for Cholera Prevention and Control], CDC, slides at back are dated 11/17/2010. Page 7 states " . . . Continue to breastfeed your baby if the baby has watery diarrhea, even when traveling to get treatment. Adults and older children should continue to eat frequently."</ref> In a 2005 publication for doctors regarding the treatment of diarrhea, the World Health Organization states: "When food is given, sufficient nutrients are usually absorbed to support continued growth and weight gain. Continued feeding also speeds the recovery of normal intestinal function, including the ability to digest and absorb various nutrients. In contrast, children whose food is restricted or diluted lose weight, have diarrhea of longer duration, and recover intestinal function more slowly."<ref name=WHOtreatmentdiarrhoea2005>[http://whqlibdoc.who.int/publications/2005/9241593180.pdf The Treatment Of Diarrhea, A manual for physicians and other senior health workers]<br>World Health Organization, 2005. See page 9 (13 in PDF) for home products and recipes that can be used to treat and prevent dehydration. See chapter "8. Management Of Diarrhea With Severe Malnutrition," pages 22-24 (26-28 in PDF). This manual is quite emphatic about the importance of continuing to feed the patient with page 10 (14 in PDF) stating: "Food should ''never'' be withheld and the child's usual foods should ''not'' be diluted. Breastfeeding should ''always'' be continued."</ref>

[[Zinc]] supplementation<ref name=who_ort_gen>{{cite web|author=[[WHO]]|title = The International Pharmacopoeia|url=http://www.who.int/medicines/publications/pharmacopoeia/ors/en/|accessdate=2008-07-15}}</ref> is recommended for the management of diarrheal disease in addition to ORS, particularly for pediatric patients. For children under five, zinc supplementation significantly reduces the severity and duration of diarrhea and is strongly recommended as a supplement with ORS for dehydrated children.<ref name=who_manual>{{cite book|author = [[WHO]]| title = The treatment of diarrhea: A manual for physicians and other senior health workers|year = 2005| isbn = 92-4-159318-0|id = WHO/FCH/CAH/05.1|url = http://whqlibdoc.who.int/publications/2005/9241593180.pdf|accessdate = 2009-02-16|format = pdf}}</ref> Preparations are available as a [[zinc sulfate]] solution for adults,<ref name=adult_zinc_sol>{{cite web|author = [[WHO]]|title=Zinc Sulfate for ORS for adults|url=http://www.who.int/entity/medicines/publications/pharmacopoeia/QAS07_194rev1Zinc-sulf_FINAL.pdf|accessdate=2008-07-15|format=pdf}}</ref> a modified solution for children,<ref name=peds_zinc_sol>{{cite web|author=[[WHO]]|title=Pediatric zinc sulfate oral solution|url=http://www.who.int/entity/medicines/publications/pharmacopoeia/QAS07_195rev1Zinc-sulf-oral-solFINAL.pdf|accessdate=2008-07-15|format=pdf}}</ref> and also a tablet form for children.<ref name=peds_zinc_tablet>{{cite web|author=[[WHO]]|title=Pediatric zinc sulfate tablets|url=http://www.who.int/entity/medicines/publications/pharmacopoeia/QAS07_193_rev1Zinc-sulf-tabFINAL.pdf|accessdate=2008-07-15|format=pdf}}</ref>

===Treatment when malnourished===
The treatment of diarrhea and dehydration in child or adult who is also malnourished is somewhat different from standard treatment. Dehydration may be over-estimated in a marasmic/wasted child and under-estimated in a kwashiorkor/edematous child. The diagnosis is based instead on whether the person has been having diarrhea.<ref name=BangladeshGuideMalnourishedChildren/><ref name=WHOtreatmentdiarrhoea2005/> The standard reduced-osmolarity oral rehydration solution needs to be modified so that it will have somewhat less salt and somewhat more sugar and potassium than standard in order to produce what is called a Rehydration Solution for Malnutrition (ReSoMal). Or, if diarrhea is severe, the standard reduced-osmolarity solution can be used.<ref name=BangladeshGuideMalnourishedChildren>[http://www.unicef.org/bangladesh/SAM_Guideline.pdf National Guidelines for the Management of Severely Malnourished Children in Bangladesh], Institute of Public Health Nutrition, Directorate General of Health Services, Ministry of Health and Family Welfare, Government of the People's Republic of Bangladesh, May 2008. See esp. pages 21-22 (pages 22-23 in PDF)</ref> In addition, the World Health Organization recommends that all malnourished persons with diarrhea be treated with a course of broad-spectrum antibiotics.<ref name=WHOtreatmentdiarrhoea2005/> Supplemental zinc is still recommended, and a dehydrated person should still continue to be given food.<ref name=WHOtreatmentdiarrhoea2005/>

== Physiological basis ==
Fluid from the body is normally pumped into the [[intestine|intestinal]] [[Lumen (anatomy)|lumen]] during digestion. This fluid is typically [[isosmotic]] with [[blood]] because it contains a high concentration of [[sodium]] (approx. 142 m[[equivalent (chemistry)|Eq]]/L). A healthy individual will secrete 20-30 [[gram]]s of sodium per day via intestinal secretions. Nearly all of this is reabsorbed by the intestine, helping to maintain constant sodium levels in the body ([[homeostasis]]).<ref name=guyton11_814>{{Cite book | author=Guyton, Arthur C.; Hall, John E. | title=Textbook of Medical Physiology | year=2006 | publisher=Elsevier Saunders | location=Philadelphia | isbn=0-7216-0240-1 | pages=814–816}}</ref>

Because there is so much sodium secreted by the intestine, without intervention, heavy continuous diarrhea can be a very dangerous and potentially life-threatening condition within hours. This is because liquid secreted into the intestinal lumen during diarrhea passes through the gut so quickly that very little sodium is reabsorbed, leading to very low sodium levels in the body (severe [[hyponatremia]]).<ref name=guyton11_814 /> This is the motivation for sodium and water replenishment via ORT.

Sodium absorption via the intestine occurs in two stages. The first is at the outermost cells (intestinal [[epithelial]] cells) at the surface of the intestinal lumen. Sodium passes into these outermost cells by [[co-transport]] via the [[SGLT1]] protein.<ref name=guyton11_814 /> From there, sodium is pumped out of the cells ([[basolateral membrane|basal]] side) and into the [[extracellular space]] by [[active transport]] via the [[sodium potassium pump]].<ref name=cps_ors>{{cite journal|author=Canadian Paediatric Society, Nutrition Committee | title = Oral rehydration therapy and early refeeding in the management of childhood gastroenteritis|journal = Paediatrics & Child Health | year = 2006| volume = 11|issue = 8|pages=527–531|url = http://www.cps.ca/english/statements/N/N06-01.htm|accessdate = 2009-02-17}}</ref><ref name=guyton11_330>{{Cite book | author=Guyton, Arthur C.; Hall, John E. | title=Textbook of Medical Physiology | year=2006 | publisher=Elsevier Saunders | location=Philadelphia | isbn=0-7216-0240-1 | pages=330}}</ref>

The co-transport of sodium into the epithelial cells via the [[SGLT1]] protein requires [[glucose]] or [[galactose]].{{Citation needed|date=December 2011}} Two sodium ions and one molecule of glucose/galactose are transported together across the [[cell membrane]] through the SGLT1 protein.{{Citation needed|date=December 2011}} Without glucose or galactose present, intestinal sodium will not be absorbed.<ref name=guyton11_814 /> This is the reason glucose is included in ORSs. For each cycle of the transport, hundreds of water molecules move into the epithelial cell, and this brings about the rehydration.{{Citation needed|date=December 2011}}

== References ==

{{reflist|30em}}

{{cholera}}
{{Gastroenterology}}

[[Category:Body water]]
[[Category:Cholera]]
[[Category:Development]]
[[Category:Gastroenterology]]
[[Category:Medical treatments]]
[[Category:World Health Organization essential medicines]]

[[de:WHO-Trinklösung]]
[[es:Sales de rehidratación oral]]
[[fa:او آر اس]]
[[fr:Soluté de réhydratation oral]]
[[id:Oralit]]
[[ml:ഓറൽ റീഹൈഡ്രേഷൻ ചികിത്സ]]
[[nl:Oraal rehydratiemiddel]]
[[ja:経口補水液]]
[[pt:Soro caseiro]]
[[sl:Raztopina za peroralno rehidracijo]]
[[fi:Oraalinen nestehoito]]
[[sv:Vätskeersättning]]