Medicines for Dehydration

What it is

Dehydration happens when the body loses more water and fluids than it takes in, so there is not enough fluid for the body to work normally. It is common and can happen for many reasons — not drinking enough (particularly in hot weather, during exercise, or when unwell), losing extra fluid through sweating, vomiting or diarrhoea, having a fever, or passing a lot of urine (for example with some illnesses or medicines). The young and the elderly are more vulnerable. Typical symptoms include feeling thirsty, a dry mouth, lips and eyes, passing small amounts of dark yellow, strong-smelling urine, passing urine less often than usual, feeling tired, dizzy or lightheaded, and headaches. In babies, signs can include fewer wet nappies, a sunken soft spot on the head, being drowsy or irritable, and few or no tears when crying. Mild dehydration is common and usually easily corrected by drinking more fluids. However, severe dehydration is a medical emergency — warning signs include extreme thirst, very little or no urine, a fast heartbeat or fast breathing, confusion or drowsiness, sunken eyes, feeling very unwell, or fainting — and needs urgent medical treatment, sometimes with fluids given directly into a vein (a drip). Recognising and correcting dehydration early, and seeking help when it is severe or when someone cannot keep fluids down, are the key points.

How it is treated

Mild dehydration is usually treated simply by replacing the lost fluids, and prevention is straightforward. The main measure is drinking enough fluid — water is usually ideal, and sipping fluids frequently is helpful, especially when unwell or in hot weather. When dehydration is caused by vomiting or diarrhoea, or by heavy sweating, oral rehydration solutions (available from pharmacies) can help replace lost salts and sugars as well as water, and are particularly useful for young children, older people, and those who are unwell; for a young child or baby who is unwell, a pharmacist or GP can advise on rehydration. Treating the underlying cause (for example the illness causing vomiting or diarrhoea, or a fever) and continuing to drink small amounts often are important. Preventing dehydration involves drinking regularly through the day, drinking more during hot weather, exercise, or illness, and encouraging fluids in those at higher risk. It is important to seek medical help if someone cannot keep fluids down, has signs of severe dehydration, is very unwell, is a baby or young child, an older or frail person, or has an underlying condition — severe dehydration needs urgent treatment, sometimes with fluids through a drip. The reassuring message is that mild dehydration is common and usually easily corrected by drinking fluids (with rehydration solutions where helpful), while severe dehydration is serious and needs urgent care, so recognising the warning signs matters.