Rehydration

Dehydration is the most significant health risk associated with diarrhoea. When the body loses water and essential salts (electrolytes) through frequent loose stools, it can lead to symptoms such as thirst, dry mouth, dark-coloured urine, dizziness, fatigue and, in severe cases, confusion and collapse. Replacing lost fluids and electrolytes is one of the most important parts of managing diarrhoea - in many cases, it is more important than stopping the diarrhoea itself.

Oral rehydration solutions (ORS) are specifically formulated to replace the water, sodium, potassium and glucose lost during diarrhoea. They contain a precise balance of electrolytes that promotes more effective fluid absorption than water alone. The World Health Organisation considers oral rehydration therapy one of the most important medical advances of the 20th century for its role in preventing dehydration-related illness and death worldwide.

Cloud Pharmacy stocks rehydration sachets and effervescent tablets from trusted UK brands, including Dioralyte and O.R.S Hydration. All products are dispensed by our GPhC-registered pharmacy team and delivered to your door.

Oral rehydration products are suitable for adults and, in most cases, children and older adults. They are one of the safest and most widely recommended treatments for managing dehydration. Check individual product labels for age-specific guidance.

These products may be appropriate if you are experiencing:

• Diarrhoea that has lasted more than a few hours, particularly if stools are frequent
• Signs of mild dehydration, such as increased thirst, dry mouth, darker urine, tiredness or lightheadedness
• Vomiting alongside diarrhoea, which increases the risk of dehydration
• Traveller's diarrhoea, where maintaining hydration is especially important
• Dehydration caused by excessive sweating, fever or reduced fluid intake during illness

If you are unable to keep any fluids down, have not passed urine for more than 12 hours, feel very drowsy or confused, or if a child has a sunken fontanelle, seek urgent medical attention. Severe dehydration may require treatment in hospital.

• Oral rehydration solutions should be made up exactly as directed on the packaging. Using too little water can make the solution too concentrated, while too much water dilutes the electrolytes and reduces effectiveness
• Once made up, Dioralyte sachets should be used within one hour if kept at room temperature, or within 24 hours if refrigerated. Do not reheat the solution
• O.R.S Hydration Tablets should be dissolved in the stated volume of water and consumed promptly
• Rehydration products can be used alongside anti-diarrhoeal medicines such as loperamide. Even if you are taking loperamide to reduce stool frequency, replacing lost fluids remains essential
• If you have kidney disease, heart failure, diabetes, or are on a sodium-restricted diet, speak to your pharmacist or GP before using rehydration products, as they contain electrolytes that may need to be monitored
• Continue drinking other clear fluids (water, diluted squash, clear broth) in addition to rehydration solutions

Dioralyte Blackcurrant Sachets

Dioralyte is the best-known oral rehydration brand in the UK. Each sachet contains a precise balance of sodium, potassium, glucose and citrate, which is dissolved in 200ml of water to create an effective rehydration drink. Dioralyte helps replace the essential water and body salts lost during diarrhoea and vomiting. The blackcurrant flavour makes it more palatable, which can be particularly helpful when nausea is present. Available in packs of 6 sachets.

Dioralyte Citrus Sachets

Dioralyte Citrus contains the same rehydration formula as the blackcurrant version, with a citrus flavour. The choice between flavours is purely one of personal preference; both provide the same electrolyte balance and clinical effectiveness. Available in packs of 6 sachets.

O.R.S Hydration Tablets - Blackcurrant Flavour

O.R.S Hydration Tablets are effervescent tablets that dissolve quickly in water to create a rehydration drink. They provide a balanced formula of electrolytes to replace fluids and salts lost through diarrhoea, vomiting, exercise or illness. The tablet format is particularly convenient for travel, work or use on the go, as they are compact, lightweight and easy to carry. Simply drop a tablet into a glass of water and allow it to dissolve before drinking.

O.R.S Hydration Tablets - Lemon Flavour

O.R.S Lemon Hydration Tablets contain the same rehydration formula in a lemon flavour. As with the blackcurrant variant, the choice is one of taste preference. Both are equally effective for rehydration.

During diarrhoea, the body loses not only water but also essential electrolytes, including sodium and potassium. Drinking plain water replaces the fluid but does not replace these lost salts and minerals. Without adequate electrolyte replacement, the body cannot absorb water as efficiently, and imbalances can develop that cause further symptoms such as muscle cramps, weakness and dizziness.

Oral rehydration solutions are formulated with a specific ratio of glucose to sodium that activates a co-transport mechanism in the gut wall, significantly enhancing water absorption. This is why ORS is more effective at treating dehydration than water, juice, sports drinks or other fluids.

• Step 1: Browse the product range on this page
• Step 2: Select the product you need and add it to your basket
• Step 3: Complete a short online assessment so our pharmacy team can confirm the product is suitable for you
• Step 4: Once approved, your order is dispensed and dispatched with discreet, next-day delivery available

NHS - Diarrhoea and vomiting: https://www.nhs.uk/conditions/diarrhoea-and-vomiting/
NHS - Dehydration: https://www.nhs.uk/conditions/dehydration/
NICE - Clinical Knowledge Summary: Diarrhoea - adults' assessment
NICE - Clinical Knowledge Summary: Gastroenteritis
WHO - Oral Rehydration Salts: Production of the new ORS