Diarrhoea and dehydration in children
Weigh the child, grade the dehydration, follow WHO Plan A, B or C, give ORS and zinc, keep feeding, and use antibiotics only for bloody diarrhoea or cholera.
An 11-month-old boy has had watery diarrhoea 8–10 times a day for 2 days and has vomited a few times. He is restless and irritable, drinks eagerly, his eyes are sunken, and a skin pinch goes back slowly. He weighs 8 kg.
How dehydrated is he, and how much ORS do you give?
- Danger signs firstLethargic or unconscious, cannot drink, fits, shock. Severe dehydration: Plan C now.
- Weigh the childEvery volume is calculated by weight.
- Grade the dehydrationNo, some or severe (WHO signs below).
- Follow Plan A, B or CORS by mouth or NG for most children. IV only for severe dehydration.
- Zinc for every childFor 10–14 days.
- Keep feedingContinue breastfeeding and normal food.
- Check for other problemsMalnutrition, blood in stool, fever, low sugar, other infections.
- Teach the motherHow to give ORS, danger signs, when to return.
- Severe dehydration or shock
- Lethargic or unconscious
- Cannot drink or vomiting everything
- Severe acute malnutrition
- Blood in stool with fever
- Diarrhoea for more than 14 days
| Plan A (no dehydration) | ORS after each loose stool: under 2 years 50–100 mL, 2 years and over 100–200 mL |
| Plan B (some dehydration) | ORS 75 mL/kg over 4 hours, then reassess |
| Plan C (severe) | Ringer's lactate 100 mL/kg IV: under 12 months 30 mL/kg over 1 hour then 70 mL/kg over 5 hours, 12 months and over 30 mL/kg over 30 minutes then 70 mL/kg over 2.5 hours |
| Zinc | 10 mg daily under 6 months, 20 mg daily from 6 months, for 10–14 days |
| Severe malnutrition | Different, slower rehydration. Do not use Plan C |
Check every dose against a current drug reference and your hospital protocol.
On this page
Why it matters
Diarrhoea remains a major cause of death in children under 5 in Pakistan, especially in summer and the monsoon. Almost all of these deaths are from dehydration and are preventable with ORS, zinc and continued feeding.
Grading dehydration (WHO)
- Lethargic or unconscious
- Sunken eyes
- Drinks poorly or cannot drink
- Skin pinch goes back very slowly (2 seconds or more)
- Plan C
- Restless, irritable
- Sunken eyes
- Drinks eagerly, thirsty
- Skin pinch goes back slowly
- Plan B
- Not enough signs for some or severe
- Plan A
In the case: restless, sunken eyes, drinks eagerly, slow skin pinch = some dehydration: Plan B. 75 mL/kg × 8 kg = 600 mL of ORS over 4 hours.
Plan A: treat at home
- ORS after each loose stool: under 2 years 50–100 mL, 2 years and over 100–200 mL.
- Zinc for 10–14 days.
- Continue feeding and breastfeeding. Give more fluids than usual.
- Return immediately if: not drinking or feeding, getting more unwell, fever, blood in stool, sunken eyes.
Plan B: ORS in the clinic
- ORS 75 mL/kg over 4 hours, given little and often with a cup and spoon.
- If the child vomits, wait 10 minutes, then continue more slowly.
- Continue breastfeeding.
- Reassess after 4 hours and choose Plan A, B or C again.
- If the child cannot drink, give ORS by NG tube at the same rate.
Plan C: severe dehydration
- IV access nowTwo attempts at IV. If not possible, intraosseous, or ORS by NG tube 20 mL/kg/hour for 6 hours.
- Ringer's lactate 100 mL/kgUnder 12 months: 30 mL/kg over 1 hour, then 70 mL/kg over 5 hours.
- Older children12 months and over: 30 mL/kg over 30 minutes, then 70 mL/kg over 2.5 hours.
- Repeat the first 30 mL/kgIf the radial pulse is still weak or absent.
- Reassess every 1–2 hoursSpeed up if not improving.
- Start ORS as soon as the child can drinkAbout 5 mL/kg/hour.
- Reassess at the endChoose Plan A, B or C.
Severe acute malnutrition (visible severe wasting, swelling of both feet, very low weight or MUAC below 11.5 cm): do not use Plan C or standard ORS. These children are at high risk of heart failure from fluid. Follow the severe malnutrition protocol (ReSoMal, slower rates, IV fluids only for shock).
Medicines
Home-made solution: 1 litre of clean boiled and cooled water + 6 level teaspoons of sugar + half a level teaspoon of salt. Measure carefully: too much salt is dangerous. Use packet ORS as soon as possible.
What not to give
- Antidiarrhoeals (loperamide, diphenoxylate): dangerous in children.
- Routine antibiotics or metronidazole for watery diarrhoea: most is viral. Antibiotics are only for bloody diarrhoea (dysentery), suspected cholera, or another infection.
- Routine antiemetic injections (such as promethazine).
- Fruit juices, sugary drinks and soft drinks instead of ORS: they can worsen diarrhoea.
- Stopping breastfeeding or food.
When it is not just gastroenteritis
- Blood in stool with fever: dysentery (Shigella). Antibiotic.
- Rice-water stools with severe dehydration in an outbreak: cholera. Antibiotic and urgent rehydration.
- Diarrhoea for more than 14 days: persistent diarrhoea. Check for malnutrition, infection, HIV.
- Bilious vomiting, blood and mucus ("redcurrant jelly") stool, a mass: intussusception. Surgical review.
- High fever, very unwell: sepsis, UTI, malaria, pneumonia.
Common mistakes
- Not weighing the child.
- Running IV fluids for some dehydration when ORS would work.
- Using Plan C in a severely malnourished child.
- Prescribing metronidazole syrup or loperamide for watery diarrhoea.
- Forgetting zinc.
- Telling the mother to stop feeding.
Frequently asked questions
How much ORS should be given for some dehydration?
75 mL/kg over 4 hours (WHO Plan B), then reassess.
What is the zinc dose for diarrhoea in children?
10 mg daily under 6 months and 20 mg daily from 6 months, for 10–14 days.
What is WHO Plan C?
For severe dehydration: Ringer's lactate 100 mL/kg IV. Under 12 months, 30 mL/kg over 1 hour then 70 mL/kg over 5 hours. 12 months and older, 30 mL/kg over 30 minutes then 70 mL/kg over 2.5 hours.
When are antibiotics needed for diarrhoea in children?
For bloody diarrhoea (dysentery), suspected cholera, or another bacterial infection. Most watery diarrhoea is viral and does not need antibiotics.
Test yourself
Exam-style questions on this guide, from our two question banks. Choose an answer to see why each option is right or wrong.
1. A child with diarrhoea has some dehydration. Which WHO plan is used?
Answer: Plan B. WHO Plan B for some dehydration: ORS 75 mL/kg over 4 hours, then reassess.
- Plan C: IV fluids: For severe dehydration.
- Antibiotics: Not for watery diarrhoea.
- Nil by mouth: Harmful.
- Plan A: home ORS only: That is for no dehydration.
2. A child has bloody diarrhoea and fever. Which antibiotic is preferred in Pakistan?
Answer: Azithromycin. Shigella dysentery: azithromycin is preferred because of fluoroquinolone resistance.
- Ciprofloxacin: Shigella is often resistant.
- Amoxicillin: Resistance.
- No antibiotic: Dysentery needs treatment.
- Metronidazole: Not for shigella.
3. A severely wasted child has diarrhoea and some dehydration. What fluid approach is used?
Answer: ReSoMal, slower rates. Malnourished children have low sodium tolerance and weak hearts; ReSoMal at slower rates is used.
- Rapid IV Ringer's lactate: Dangerous.
- Plain water: Not enough electrolytes.
- Nil by mouth: Harmful.
- Standard Plan B: Risks heart failure.
4. A 22-year-old student develops acute watery diarrhoea 3 days into a trip, without blood or fever. He is drinking well. What is the main treatment?
Answer: Oral rehydration. Most acute watery diarrhoea is self-limiting (enterotoxigenic E. coli, norovirus). Oral rehydration is the mainstay. Loperamide is acceptable for non-bloody diarrhoea in adults; antibiotics (azithromycin) only for severe illness, fever or dysentery. Stool culture for bloody diarrhoea, fever, immunosuppression or prolonged symptoms. Giardia causes prolonged greasy diarrhoea and bloating — treat with metronidazole/tinidazole.
- IV ciprofloxacin: IV antibiotics are not needed for mild traveller’s diarrhoea.
- Metronidazole for 7 days: Metronidazole is for Giardia or amoebae.
- Loperamide with bloody stools: Loperamide should be avoided in bloody diarrhoea.
5. A 14-month-old (10 kg) with watery diarrhoea is restless, has sunken eyes and drinks eagerly; skin pinch returns slowly. What is the treatment?
Answer: ORS 750 mL over 4 hours + zinc. WHO classification: some dehydration (two of: restless/irritable, sunken eyes, drinks eagerly, skin pinch goes back slowly) → Plan B: ORS 75 mL/kg over 4 hours in the clinic, then reassess. Zinc 20 mg daily for 10–14 days (10 mg if < 6 months), continue feeding. Severe dehydration (lethargic, unable to drink, very slow skin pinch) → Plan C: IV Ringer’s lactate 100 mL/kg. No dehydration → Plan A at home.
- IV Ringer’s 100 mL/kg: IV fluid at 100 mL/kg is Plan C for severe dehydration.
- ORS only after each stool: Replacing stools only is Plan A for no dehydration.
- Antibiotics and fluids restriction: Restricting fluids is harmful.
6. Which receptors are most abundant in the fingertips and detect light touch and two-point discrimination?
Answer: Meissner's corpuscles. Meissner's corpuscles lie in the dermal papillae of hairless skin, especially fingertips and lips. They adapt rapidly and detect light touch and low-frequency vibration. Merkel discs (slowly adapting) also help with fine touch and texture.
- Pacinian corpuscles: Deep, detect high-frequency vibration and pressure.
- Ruffini endings: Detect skin stretch; slowly adapting.
- Free nerve endings: Detect pain and temperature.
- Muscle spindles: Detect muscle length.
7. A child has a swollen belly, pitting oedema of the legs, flaky skin, light-coloured hair streaks and a large liver. What is the diagnosis?
Answer: Kwashiorkor. Kwashiorkor is protein deficiency with relatively adequate calories. Low albumin causes oedema; fatty liver occurs because apolipoproteins for exporting fat are not made. Skin flakes like peeling paint, and hair shows the 'flag sign'. Marasmus is overall energy deficiency: severe wasting with no oedema.
- Marasmus: Wasting without oedema.
- Rickets: Bone deformities.
- Scurvy: Bleeding gums.
- Hypothyroidism: Puffy face, constipation, slow growth.
References and dose sources
- WHO: The treatment of diarrhoea, a manual for physicians and other senior health workers
- WHO fact sheet: Diarrhoeal disease
- Oral rehydration salts (ORS) dosing: MSF Essential Drugs: Oral rehydration salts (see also our oral rehydration salts (ors) dose page)
- Zinc dosing: WHO: The treatment of diarrhoea, a manual for physicians (see also our zinc dose page)
- Ringer's lactate (Hartmann's solution) dosing: Drugs.com: Lactated Ringer's dosage (see also our ringer's lactate (hartmann's solution) dose page)
- Dextrose (glucose) dosing: Drugs.com: Dextrose dosage (see also our dextrose (glucose) dose page)
- Azithromycin dosing: Drugs.com: Azithromycin dosage (see also our azithromycin dose page)
- Ondansetron dosing: Drugs.com: Ondansetron dosage (see also our ondansetron dose page)
International guidance is linked where it reflects good practice. Where your hospital’s protocol differs, follow your hospital.