Preventing Dehydration in Older Adults

Why Older Adults Are at Higher Risk

With age, the sense of thirst becomes less reliable, and the kidneys are less able to conserve water. Many older people also drink less on purpose — for example, to avoid frequent trips to the toilet, because of bladder leakage, or because getting a drink is physically difficult.

Other factors add to the risk: memory problems, difficulty swallowing, depending on others for drinks, reduced appetite, and medicines such as diuretics ("water tablets"). In a warm, humid climate, fluid is also lost through sweating, even without obvious exertion.

Situations That Increase the Risk

• Hot weather, or a hot room without good ventilation
• Fever or infection
• Vomiting or diarrhoea, even for a short time
• Reduced eating and drinking during illness
• A recent change in medicines, especially diuretics
• Recent discharge from hospital

Signs to Look Out For

In older people, dehydration often causes general and easily overlooked changes rather than obvious thirst:

• Passing less urine than usual, or dark, strong-smelling urine
• Dry mouth, lips or tongue
• Tiredness, weakness or dizziness, especially when standing up
• Headache or constipation
• New or worsening confusion, drowsiness or irritability
• Falls or unsteadiness

Urine colour can be a helpful clue but is less reliable in older people and can be affected by some medicines and vitamins. It is better to look at the whole picture — how much the person is drinking, how much urine they pass, and how they are behaving compared with usual.

Practical Ways to Encourage Drinking

• Offer drinks regularly. Offer a drink at set times — with each meal, mid-morning, mid-afternoon and in the evening — rather than waiting for the person to ask.
• Keep a drink within reach. A lightweight cup or a cup with handles or a lid may be easier to use than a glass.
• Offer drinks the person enjoys. Water is ideal, but other drinks such as weak tea, milk, soups and diluted fruit juice also contribute. Be cautious with sugary drinks in people with diabetes.
• Include foods with a high water content. Soups, porridge, curd, and fruit such as watermelon or papaya all provide fluid.
• Plan around the toilet. Encouraging most drinks earlier in the day and making the route to the toilet easy and well lit can reduce night-time worries.
• Keep a simple chart. Recording cups drunk each day helps caregivers share responsibility and notice when intake falls.

During Vomiting, Diarrhoea or Fever

Illness can cause fluid loss quickly. Offer small, frequent sips rather than large amounts at once. An oral rehydration solution (ORS), prepared exactly as directed on the packet, replaces both water and salts and is often more effective than plain water when there is diarrhoea or vomiting.

Contact a doctor early if an older person is unable to keep fluids down, has diarrhoea that is not settling, or takes medicines — such as diuretics, some blood pressure medicines or diabetes medicines — that may need to be reviewed during illness. Do not stop these medicines without advice.

When to Seek Medical Help

Related Guides

• Warning Signs in an Older Person That Need Medical Assessment
• Preventing Falls in Older Adults at Home
• How to Measure Temperature Correctly at Home
• IV Fluids at Home: When They May Be Used and When They Can Be Dangerous