Electrolytes for hiking: staying hydrated even without familiar brands

This guide isn't professional medical advice. If you have a health condition, talk to a doctor before changing your hydration routine.

Most posts you see online about electrolytes and hiking assume you've lived in your climate for years, that you shop somewhere with a full shelf of familiar sports-nutrition brands, and that your only variable is how long or hot the hike is. If you've recently moved, you're traveling long-term, or you're hiking in a country where you don't recognize a single word on the pharmacy shelf, none of those assumptions hold.

This guide explains how your approach to electrolytes for hiking should change during your first weeks in a new climate, how to tell dehydration vs hyponatremia apart when something feels off, and what to buy or mix yourself when you can't find a single familiar brand on the shelf.

What electrolytes actually do on the trail

Electrolytes are minerals like sodium, potassium, and magnesium. They carry a small electric charge that your muscles and nerves need to work. When you sweat, you lose water and electrolytes together. If you drink only water to replace what you lost, you dilute the electrolytes still in your body. That's when cramping, nausea, and confusion can start.

Sodium is the one that matters most for hikers, because it's lost in the largest amounts and it's the one most easily depleted with plain water. Potassium and magnesium matter too, but sodium is where most hiking guides start and end.

The variable nobody mentions: how long you've been in the heat

How long you've been in a hot climate directly changes how much sodium you lose to sweat, which is exactly why it matters for electrolytes and almost never comes up in hiking advice.

Your body will get used to the heat within about 7-14 days of consistent exposure, according to CDC/NIOSH guidance on heat acclimatization. As it adapts, your sweat becomes more dilute, meaning you lose less sodium per liter of sweat for the same hike. Two people can walk the same trail in the same heat and lose very different amounts of salt, depending on how many days their bodies have had to adjust.

Someone who has lived in a hot climate for months loses less salt sweating through the same hike than someone who landed a week ago. If you have just arrived somewhere warm and are still adjusting to a new climate, your body is doing more work and losing more sodium than a local hiker on the same trail, even if you're both drinking the same amount of water. That's extra sodium you need to replace with electrolytes.

A 2025 heat adaptation study verifies the timeline in general: most adaptations take place within the first week, and the process is mostly finished after 10-14 days of consistent heat exposure. The same review cautions that older studies claiming precise day-by-day percentages were often based on very small groups, so treat the table below as a rough guide to when adaptation happens.

In your first week in a new hot climate, add electrolytes to hikes where you normally wouldn't bother. Your sodium loss is higher than the temperature or the trail length would suggest, simply because your body hasn't caught up yet.

Dehydration vs hyponatremia: two opposite problems

Getting dehydration vs hyponatremia right matters, because the two conditions look similar early on but need opposite treatment. 

Dehydration is too little water relative to sodium. 

Hyponatremia is too little sodium relative to water, usually from drinking large amounts of plain water on a long, hot hike without replacing salt. 

Both conditions can cause headache, nausea, and confusion, which is exactly what makes them easy to mix up in the moment. 

Treating hyponatremia with more plain water makes it worse

The Wilderness Medical Society's clinical practice guidelines on exercise-associated hyponatremia confirm that this happens when you drink water or sports drinks without replacing enough sodium. Their research found that up to 50% of endurance athletes screened show some degree of hyponatremia, which makes it far more common than most hikers assume.

The same guidelines recommend drinking to thirst rather than on a fixed schedule, and replacing sodium through food or electrolytes during long, hot efforts rather than relying on water alone.

The practical takeaway: if you can't tell which one it is, treat it as sodium loss first and reach for electrolytes rather than more plain water. That helps if it's dehydration, and it stops hyponatremia from getting worse.

If your symptoms are severe or someone nearby becomes confused or loses consciousness, that's a medical emergency. Get help rather than trying to self-treat on the trail.

What electrolytes to buy when you don't recognize any of the labels

Most guides ranking the best hiking electrolytes list popular sports-nutrition brands. That's fine if you're somewhere where many are available, like when you're hiking the Tour du Mont Blanc or exploring hiking trails in Madeira, where you have access to pharmacies and sports stores.

However, it's useless if you're standing in a pharmacy in a country where you don't read the language and none of those brands exist on the shelf.

Look for the ingredient names rather than a brand

What you want on the label is sodium chloride or sodium citrate, potassium chloride, and sometimes magnesium. These terms are close to identical across most Latin-alphabet languages, so they're easier to spot than a brand name.

Oral rehydration salts, the cheap sachets sold in pharmacies worldwide to treat dehydration from diarrhea, are one of the best-kept secrets in hiking hydration. They're formulated to the World Health Organization's reduced-osmolarity ORS standard: 2.6 g sodium chloride, 1.5 g potassium chloride, 2.9 g trisodium citrate, and 13.5 g glucose per liter. 

That's more sodium than most sports drinks contain; they're sold almost everywhere, and a box of 20 sachets typically costs 3 to 5 €. Look for them under names like Suero Oral in much of Latin America, ORS in South and Southeast Asia, generic "rehydration salts" in European pharmacies, or an ORS rehydration solution label in some markets.

A recipe for hiking hydration with no label to read

If you can't find any of the above, you can make an effective rehydration drink with ingredients sold in every country: water, salt, and sugar. 

Mix 1 liter (34 fl oz) of water with 6 level teaspoons of sugar and half a level teaspoon of salt. Add a squeeze of lime or orange if you have it, which helps with taste and adds a small amount of potassium.

This isn't identical to the pharmaceutical oral rehydration salt formula, since it skips the potassium and citrate, but it's the standard sugar-salt substitute recommended for when ORS packets aren't available.

It tastes plain, not great, but it works, and you can make it with ingredients from any corner shop on earth.

How much electrolytes for hiking you need to take and when

Electrolyte needs scale with heat, hike length, and how long you've been acclimatizing, not just one of those factors on its own.

Sip regularly rather than drinking large volumes at once, for both plain water and electrolyte mixes. Large single doses of water without sodium are exactly what pushes toward hyponatremia on long, hot days.

Summing up: a short electrolytes checklist

Before a hot or long hike, especially early in a new climate, run through this:

• Do I know how many days I've actually spent in this heat, not just how long I've been in the country?
• Do I have electrolytes with me, not just water?
• If I can't find my usual brand, do I know what to look for on a local label?
• Do I know the difference between dehydration and hyponatremia symptoms if something feels off?
• Have I checked the current heat advisory or trail conditions for today, not just a general guide like this one?

If you can't check off every item, especially the first one, then treat the hike as riskier than it looks: find or make electrolytes before you go, whether that's a local ORS packet, salt tablets, or the DIY recipe, and start using them before symptoms show up.