How much water does an infant need?

Infants need more water when they sweat excessively due to high fever or when they vomit repeatedly or have prolonged diarrhea. In these conditions, infants may get dehydrated quickly, much faster than older children or adults.

In order to prevent dehydration, infants need to drink additional fluid besides their regular food. They should never drink plain water, tea, fruit juice or soft drinks but only rehydration solutions with specific amounts of electrolytes and sugar. Pre-prepared "oral rehydration solutions" (ORS) of various brands with slightly different amounts of sodium, potassium and glucose are available in drug stores and bigger markets without prescription.

When you do not have an oral rehydration solutions available, you can quickly prepare one at home ^[2]. Put one liter of water in a pot and add 1/2 teaspoon of salt (3 grams of sodium chloride) and six level teaspoons of table sugar (about 25 grams of sucrose), mix well, boil and cool down to drinking temperature.

Small differences in the salt and sugar amounts should not be harmful, but using, for example, twice too little or too much of each ingredient can be dangerous. If you are not confident about measuring, ask someone for help.

Do not wait for a baby to get dehydrated but start giving the solution right after the onset of vomiting or diarrhea. Offer the solution by a spoon rather than a bottle, because a baby can suck too much solution from a bottle at once and then vomit it. Try to give one teaspoon of a solution every minute or so. Continue to give a solution even if a baby vomits repeatedly. If a baby refuses to drink or if you feel that he or she loses more fluid than you can provide it, take him or hem to a doctor as soon as possible.

Symptoms of dehydration in an infant ^[2]:

• Dry lips and mouth
• Sunken eyes
• Depressed fontanel (the soft spot on the top of the head)
• More than six hours without a wet diaper, dark urine
• Unusual sleepiness

You can also check the infant's skin turgor. You pinch the skin on his or her abdomen and release it; the skin fold that needs more than a second to flatten speaks for dehydration.

NOTE: Dehydration due to prolonged diarrhea from a simple Rotavirus infection (gastroenteritis, stomach flu) can be life threatening if not treated by rehydration promptly. According to World Health Organization (WHO), about 760,000 children under age of five die each year from diarrhea.

Water intoxication means a drop of blood sodium levels due to excessive intake of plain water, tea or fruit juice, which contain only a little sodium. As little as one cup (237 mL) of water, in addition to breastfeeding or formula, can cause water intoxication in an infant younger than 6 months. Symptoms include excessive urination (>6-8 wet diapers a day), swelling around the eyes, irritability, vomiting and seizures.

Example: A newborn girl was fed by 2 oz of milk formula and 4 oz of water every 4 hours; she developed hyponatremia with seizures and she lost consciousness. Luckily, she was successfully treated with no complications.

NOTE: Do not give plain water to an infant and do not dilute formula from any reason.

Gripe water is usually used in small amounts, so it should not be dangerous as such, but there is insufficient evidence about its effectiveness in treatment of abdominal colic.

References:

1. Myths and facts about breastfeeding  State of New Jersey, Department of Health
2. Oral rehydration solutions, made at home  Rehydration Project
3. Dehydration in infants and toddlers  eHealthStar

Thumbnail image source: Wikihow  (Creative Commons licence)