Best Hydration Tablets for Travel in the UK
You land after a long-haul flight with a dry throat, a dull head and the sense that you've been sitting in a tumble dryer. Or you've spent a day dragging a suitcase between trains and realise you've had one coffee and half a bottle of water since breakfast. Travel makes it easy to drink less than you need.
Hydration tablets are one of the simplest fixes. A tube weighs almost nothing, fits in a coat pocket and turns any bottle of water into something you'll want to drink. This guide covers why travel dehydrates you, what to look for in travel hydration tablets and how to use them on the move.
Why travel leaves you dehydrated
Dry cabin air
The air on a plane is drawn in from outside at altitude, where it holds very little moisture. Cabin humidity is typically far lower than in a normal home, so you lose more water through your breath and skin over a long flight.
Drinking less than usual
Security queues, small cabin cups and not wanting to climb over your neighbour all add up. Many people drink less on travel days without noticing. Coffee and alcohol on board don't help. For context, the European Food Safety Authority puts adequate total water intake at about 2 litres a day for women and 2.5 litres for men, from food and drink combined (EFSA: dietary reference values for water). Hitting that on a travel day takes a bit of planning.
Heat and walking
A city break in summer can mean 20,000 steps in the sun. The NHS lists hot weather and sweating among the main causes of dehydration, along with drinking alcohol (NHS: dehydration).
Sitting still for hours
Long trips also raise the risk of blood clots. The NHS advises drinking plenty of water, avoiding alcohol and moving around on long flights (NHS: deep vein thrombosis).
What to look for in travel hydration tablets
- A strong, compact tube. It should survive the bottom of a bag and close properly so tablets stay dry.
- Effervescent tablets. They dissolve in a couple of minutes in a bottle of water, with no scoop or shaker.
- A balanced mineral profile. For travel days, which are usually low on sweat, a potassium-led formula with modest sodium suits most people. If you're trekking in heat, look for more sodium.
- Low sugar. You're sitting still, so you don't need a lot of carbohydrate.
- A flavour you like. You'll drink more of something that tastes good.
- Clear labelling. The amount per serving of each mineral, and how many tablets make a serving.
Taking tablets through airport security
Hydration tablets are solids, so the 100ml liquids rule doesn't apply to them. Keep them in their original labelled tube in your hand luggage. Buy or refill a water bottle once you're airside and add your tablets then. If you're flying outside the UK, check the rules for your destination, as some countries are stricter about supplements.
A simple plan for travel days
Before you leave
Start the day with a glass of water or an electrolyte drink, and eat properly before you set off.
On the plane or train
Aim for a glass of water every hour or so. Have one electrolyte serving partway through a long flight, and go easy on alcohol and coffee.
When you arrive
Have another serving if you feel flat, then keep sipping water through the afternoon. Light, regular drinks work better than downing a litre at once.
On hot days away
Carry a bottle and a tube when you're out walking. Eat salty snacks if you've been sweating heavily, and rest in the shade during the hottest part of the day.
HIRO Hydration for travel
HIRO electrolyte tablets come in slim tubes of 20 effervescent tablets. Two tablets dissolved in about 300ml of water make one serving, so a tube gives you 10 drinks.
| Per serving (2 tablets) | Amount |
|---|---|
| Potassium | 300mg |
| Chloride | 180mg |
| Sodium | 116mg |
| Magnesium | 65mg |
| Zinc | 2mg |
| Manganese | 0.4mg |
| Energy / carbohydrate | 20 kcal / 5g |
The formula is lower in sodium and higher in potassium than a sports drink, which suits travel days where you're mostly sitting. Potassium and magnesium support normal muscle and nerve function. The tablets are vegan and sucralose-sweetened, and they come in three flavours: Lemon & Elderflower, Watermelon and Ginger & Lemongrass. BBC Good Food voted them Best Tasting Electrolyte Tablets, and The Independent named them Best Hydration Flavours in 2026.
If you're heading somewhere hot to hike or cycle long distances and you sweat heavily, pack a higher-sodium sports electrolyte for those days as well.
Which pack to take
- A weekend away: one tube from a Multi-Flavour Triple Pack covers it. Leave the other two at home.
- A two-week holiday: take two tubes so you have a serving a day.
- Frequent flyers: keep a tube permanently in your travel washbag. A subscription delivered every three months takes 25% off and ships free.
Our electrolyte tablets price guide works out the cost per serving for every pack.
A simple travel hydration kit
Pack these in the outside pocket of your hand luggage so they're easy to reach:
- An empty reusable bottle, around 500ml to 750ml, to fill once you're past security.
- A tube of hydration tablets in its original packaging.
- A couple of salty snacks, such as nuts or crackers, for long days walking in the heat.
- Lip balm and moisturiser, which help with the dry cabin air.
On a road trip, keep a larger bottle in the car door and stop every couple of hours. That's good for your concentration behind the wheel too: the Highway Code advises a break of at least 15 minutes every two hours on long drives.
Mistakes travellers make
Waiting until you're thirsty. On a dry flight, thirst lags behind. Drink little and often.
Relying on coffee and wine. Both are fine in moderation, but they shouldn't be your main drinks on a travel day.
Doubling the dose to catch up. One serving at a time is enough. Make up the rest with water.
Packing tablets loose. Effervescent tablets react with moisture. Keep them in their tube with the lid closed.
If you have a kidney condition, take medication that affects potassium or are pregnant, check with your GP or pharmacist before using electrolyte products regularly. HIRO isn't recommended for anyone under 18.
The short version
Travel dries you out through cabin air, heat and simply drinking less. A tube of electrolyte tablets makes it easier to keep drinking, wherever you are. For most trips, a potassium-led everyday tablet like HIRO is all you need. Browse the full electrolyte tablets range, and every order is covered by our 60-day money-back guarantee.
Frequently asked questions
Can I take hydration tablets on a plane?
Yes. They're solid, so the liquids limit doesn't apply. Keep them in their labelled tube in your hand luggage.
How many should I take on a long-haul flight?
One HIRO serving (two tablets in about 300ml of water) partway through the flight, plus plain water every hour or so, works well for most people.
Do hydration tablets help with jet lag?
They can help you stay hydrated, which may make you feel less rough when you land. They don't reset your body clock. Daylight, sleep timing and meals at local times do that.
Can I use hydration tablets on a road trip?
Yes. Keep the tube somewhere cool and dry, and make up a bottle at each stop rather than leaving mixed drinks in a hot car.
Are HIRO tablets suitable for hot countries?
Yes, for everyday use and moderate activity. If you'll be sweating heavily for hours, add a higher-sodium sports electrolyte for those days.