What is the best treatment for dehydration?

Treatment of Dehydration

Oral rehydration solution (ORS) is the first-line treatment for mild to moderate dehydration, while severe dehydration requires immediate intravenous fluid resuscitation followed by transition to ORS. 1

Assessment and Stratification

Before initiating treatment, determine the severity of dehydration through physical examination:

• Mild dehydration (3-5% fluid deficit): Increased thirst and slightly dry mucous membranes 1
• Moderate dehydration (6-9% fluid deficit): Loss of skin turgor, dry mucous membranes, and decreased urine output 1, 2
• Severe dehydration (≥10% fluid deficit): Severe lethargy or altered consciousness, prolonged skin tenting, and signs of shock 1

The most reliable clinical indicators are rapid deep breathing, prolonged skin retraction time, and decreased perfusion—more so than sunken fontanelle or absence of tears 1

Treatment Protocol by Severity

Mild Dehydration (3-5% fluid deficit)

Administer ORS containing 50-90 mEq/L of sodium at 50 mL/kg over 2-4 hours 1, 2

• Start with small volumes (one teaspoon) using a teaspoon, syringe, or medicine dropper, then gradually increase as tolerated 2
• Replace ongoing losses: 10 mL/kg of ORS for each diarrheal stool and 2 mL/kg for each vomiting episode 2
• For children <2 years: Give 50-100 mL of ORS after each stool 2
• For older children: Give 100-200 mL after each stool 2
• For adults: As much as they want, though those failing to respond promptly should be reassessed to exclude cholera 2

Moderate Dehydration (6-9% fluid deficit)

Administer ORS containing 50-90 mEq/L of sodium at 100 mL/kg over 2-4 hours 1, 2

• Use the same gradual administration approach as mild dehydration 2
• Reassess hydration status after 2-4 hours; if still dehydrated, reestimate the fluid deficit and restart rehydration therapy 2
• For infants unable to drink but not in shock, use nasogastric tube administration at 15 mL/kg/hour 2
• Continue replacing ongoing losses as described above 2

Severe Dehydration (≥10% fluid deficit)

This is a medical emergency requiring immediate IV rehydration with boluses of Ringer's lactate solution or normal saline 1

• Administer 60-100 mL/kg of 0.9% saline in the first 2-4 hours to restore circulation 3
• Once circulation is restored and the patient is stable, transition to ORS given in small quantities over 6-8 hours 3
• For infants in shock, nasogastric tube should only be used if IV equipment and fluids are not available 4

ORS Selection

In the United States, several commercial formulations are available:

• Pedialyte (45 mEq/L sodium) and Ricelyte (50 mEq/L sodium) are the most widely used solutions 4
• These lower-sodium solutions (40-60 mEq/L) are appropriate for maintenance and prevention of dehydration 4
• When using fluids with >60 mEq/L sodium for maintenance, also provide low-sodium fluids such as breast milk, diluted formula, or water to prevent sodium overload 4
• When the rate of purging is very high (>10 mL/kg/hour), solutions with 75-90 mEq/L are recommended for rehydration 4

Nutritional Management During Treatment

Feeding should begin as soon as appetite returns, and "resting the bowel" through fasting should be avoided 1

• Breastfed infants: Continue nursing on demand throughout the illness 1, 2
• Bottle-fed infants: Use full-strength, lactose-free, or lactose-reduced formulas immediately upon rehydration 1, 2
• Children >4-6 months: Offer age-appropriate foods every 3-4 hours as tolerated, including energy-rich, easily digestible foods 4, 2
• After diarrhea stops, give one extra meal each day for a week 4

Common Pitfalls to Avoid

• Do not use soft drinks for rehydration due to their high osmolality 1
• Antimicrobial drugs are contraindicated for routine treatment of uncomplicated watery diarrhea unless specific pathogens (cholera, Shigella, amoebic dysentery, acute giardiasis) are identified 4
• Anti-diarrheal agents are contraindicated for treatment of diarrheal disease 1
• Do not delay feeding until diarrhea stops—early feeding reduces severity, duration, and nutritional consequences 4

When to Switch to IV Therapy

Consider intravenous fluids if there is:

• Progression to severe dehydration 2
• Shock or altered mental status 2
• Failure of ORS therapy 2
• Inability to tolerate oral or nasogastric intake 5

Use isotonic solutions such as lactated Ringer's or normal saline 2

Monitoring Response

Regularly assess the following:

• Clinical signs including skin turgor, mucous membrane moisture, and mental status 2
• Stool frequency and consistency 2
• Weight changes throughout therapy 2
• Reassess hydration status after 3-4 hours and continue treatment according to the degree of dehydration at that time 4