In this article
From pharmacy rehydration salts to sports powders, fizzy tablets, coconut water and recovery sachets — what's actually in them, what the evidence says matters, and which one suits the job you need done.
"Electrolyte drink" covers a lot of ground. A sachet of Dioralyte, a tub of SiS, a High5 tablet, a carton of coconut water and a bottle of Lucozade Sport are all sold on the same word, and they are nothing like each other. Some are medicines designed for a stomach bug. Some are fuel for a three-hour ride. Some are mostly water with a pleasant taste and a marketing budget.
The good news is that you don't need to take anyone's word for it. The thing that matters most in a rehydration drink — sodium — is printed on every label, and so is the sugar. This guide puts eight widely available UK options side by side using those labels, explains what the research says a rehydration drink needs, and tells you which one to reach for when you're rehydrating after exercise, recovering from a bug, or facing the morning after.
How we compared them (and a disclosure)
First, the disclosure: Humans Against is our product. It's in this comparison because it's a UK electrolyte sachet and leaving it out would be odd, but we've put its numbers in the same table as everyone else's, including the ones that don't flatter it. Where a competitor does a job better than we do, we say so.
Second, the method. We have not run taste tests or lab assays. Every figure below comes from the product's own label, patient information or official product page, read in October 2026, and we've given the source for each. Prices are the retailer or brand prices we found on the same day; they move, so treat them as a guide. Where we couldn't confirm a figure, we've left it blank rather than guess.
Third, the yardstick. We compare drinks on sodium per serving and per litre (the number that decides whether the fluid stays in you), sugar per serving, what else is in the drink, and cost per serving. We also say what each product is actually designed for, because a drink that is "worst" for a marathon can be exactly right for a stomach bug.
What to look for in an electrolyte drink
Sodium: the number that matters most
Sodium is the electrolyte that makes water count. When you drink fluid with enough sodium in it, your kidneys hold on to more of the water instead of sending it straight back out as urine. This has been measured directly: in a study at Aberdeen, volunteers who had sweated out about 2% of their body weight were given drinks containing either 23 or 61 mmol/L of sodium, in volumes from half to twice what they'd lost. At any given volume, less urine was produced after the higher-sodium drink, and the only trials that left volunteers back in positive fluid balance were the ones combining the higher-sodium drink with a volume well above what had been lost (Shirreffs et al., 1996). An earlier study from the same group found that a near-sodium-free drink left volunteers well short of balance six hours later, while drinks at 52 and 100 mmol/L brought them back to even (Maughan & Leiper, 1995).
To put those numbers in label terms, 60 mmol/L of sodium is about 1.4 g per litre. That is roughly what pharmacy rehydration salts deliver, and it is a lot more than most sports drinks or fizzy tablets. The practical rule: for serious rehydration — a stomach bug, a long hot session with heavy sweating — look for a drink in the pharmacy-salts range. For topping up through the day, or the morning after, a lower-sodium drink is fine, as long as you know that's what you're buying.
For context, the NHS advises adults to eat no more than 6 g of salt a day (about 2.4 g of sodium). Most of us get more than that from food, which is why a high-sodium drink is a tool for specific situations, not a daily habit.
Glucose: a little helps, a lot is fuel
The cells lining your small intestine absorb sodium and glucose together, and water follows. That pairing is the whole idea behind oral rehydration solution (ORS), and it's why the WHO's reduced-osmolarity formula contains 75 mmol/L of glucose — 13.5 g per litre — alongside 75 mmol/L of sodium (WHO, 2006). That's a deliberately modest amount of sugar whose job is absorption, not energy.
Sports drinks are different. They typically run at 4–8 g of carbohydrate per 100 ml because they are built to fuel exercise that lasts over an hour. The American College of Sports Medicine's position stand notes that drinks containing both electrolytes and carbohydrate can offer benefits over water alone in some circumstances, and that fluid plans should be individualised because sweat rates vary so much (Sawka et al., 2007). The sugar isn't a flaw in a sports drink; it's the point. It only becomes a flaw when you're not exercising.
Potassium and magnesium: nice to have, not the headline
Potassium is the main electrolyte inside your cells; the NHS puts the adult requirement at about 3,500 mg a day, and food — potatoes, beans, bananas, yoghurt, leafy greens — is how almost all of it arrives. No drink in this list provides more than a modest fraction of that, so potassium content is not a good reason to pick one drink over another.
Magnesium is worth a look if you want more from a sachet than salt and sugar. It contributes to electrolyte balance, to normal muscle function and to the reduction of tiredness and fatigue — those are authorised claims on the GB register — and alcohol measurably increases the amount of magnesium you pass in urine. We've written up the evidence in Electrolyte Science: How Minerals Support Recovery. Most sports drinks and pharmacy salts contain little or none; some tablets and sachets contain a meaningful dose.
What it's designed for
This is the question that cuts through most of the marketing. A medicine for diarrhoea, a fuel drink for cyclists, a zero-calorie tablet for a gym bag and a vitamin-and-mineral recovery sachet are solving different problems. The right question isn't "which is best?" but "best for what?"
The main types, and what each is built for
Oral rehydration salts (Dioralyte, O.R.S)
These are the clinical standard, developed to replace fluid lost to diarrhoea and vomiting. High sodium, modest glucose, potassium and citrate in proportions that have been refined over decades. They taste salty because they are salty. If you've had a stomach bug, this is the category to buy, and your pharmacist can advise.
Sports electrolyte powders (SiS, Precision Fuel & Hydration)
Built for endurance exercise. Some, like SiS GO Electrolyte, are carbohydrate drinks with electrolytes added; others, like Precision's PH range, are sodium-first and let you choose the strength. Either way, they assume you're sweating hard for an hour or more.
Zero-sugar effervescent tablets (High5 ZERO)
Drop one in a bottle. Low or no calories, moderate sodium, portable and cheap per serving. Good for everyday training, hot days and travel; not enough sodium per litre for serious rehydration after illness.
Coconut water
Naturally high in potassium, naturally low in sodium, and about as sugary as a sports drink. Pleasant, but not an electrolyte drink in the sense that matters for rehydration — more on that below.
Ready-to-drink sports drinks (Lucozade Sport)
Convenient and everywhere. Modest sodium, carbohydrate for fuel, and you're paying to ship water. Useful on a hot touchline; not a rehydration tool.
Recovery sachets (Humans Against)
A different category again: a food supplement that pairs a gentle dose of sodium and glucose with magnesium, vitamin C, B vitamins and other actives, designed for the morning after rather than for a marathon or a stomach bug. Low in sugar, not sugar-free, and — it bears repeating — not a medical ORS.
Eight UK electrolyte drinks, compared by the label
All figures are per serving as the label directs, with the sodium-per-litre figure worked out from the serving volume. "Sodium" means elemental sodium, not sodium chloride; where a label gives salt or sodium chloride instead, we've converted it and said so.
| Drink | Serving | Sodium per serving | Sodium per litre | Sugar per serving | Cost per serving |
|---|---|---|---|---|---|
| Dioralyte (sachet) | 1 sachet in 200 ml | ≈300 mg | ≈1,500 mg (≈65 mmol/L) | 3.56 g glucose | Not checked |
| O.R.S Hydration Tablets | 2 tablets in 200 ml | 277 mg | ≈1,385 mg (≈60 mmol/L) | 3.4 g | ≈45–65p |
| Precision Fuel & Hydration PH 1000 | 1 sachet (20 g) in 500 ml | 500 mg | 1,000 mg (≈43 mmol/L) | 16 g | ≈£1.37 |
| SiS GO Electrolyte | 40 g in 500 ml | 200 mg | 400 mg (≈17 mmol/L) | 6.7 g (36 g carbohydrate) | ≈£1.33 |
| High5 ZERO | 1 tablet in 750 ml | 250 mg | ≈333 mg (≈14 mmol/L) | 0 g | ≈30–40p |
| Humans Against | 1 sachet (9 g) in 200 ml | ≈79 mg (from 200 mg sodium chloride) | ≈395 mg (≈17 mmol/L) | 3 g glucose | ≈£3.24 |
| Lucozade Sport (Orange) | 500 ml bottle | ≈250 mg (50 mg per 100 ml) | ≈500 mg (≈22 mmol/L) | Contains glucose syrup; see label | ≈£1.65–£1.85 |
| Vita Coco coconut water | 330 ml carton | 65 mg | ≈200 mg (≈9 mmol/L) | 17 g | Not checked |
Two things jump out. The pharmacy products carry three to four times the sodium per litre of most sports drinks and tablets — and about half as much again as the strongest sports mix here — which is why they're the ones that work for a stomach bug. And the "sports" products split cleanly into fuel drinks (SiS, PH 1000, Lucozade) with real carbohydrate in them and low-sugar drinks (High5 ZERO, Humans Against) that aren't trying to feed you. Now the detail.
Dioralyte
What it is: a licensed UK oral rehydration medicine for replacing fluid and electrolytes lost to diarrhoea. Each sachet contains glucose 3.56 g, sodium chloride 0.47 g, potassium chloride 0.30 g and disodium hydrogen citrate 0.53 g, which the patient information sums up as approximately 300 mg of sodium per sachet, dissolved in 200 ml of water.
Where it wins: the highest sodium per litre in this list, in the proportions clinical rehydration is built on. If you've been ill, this is the one.
Where it doesn't: it tastes like a medicine, because it is one. It contains no magnesium or vitamins, and a 200 ml serving is small if you're trying to get a lot of fluid back on board after a hot run. Follow the pack and ask the pharmacist if you're unsure.
O.R.S Hydration Tablets
What it is: the same idea as Dioralyte in a fizzy tablet, sold over the counter rather than as a licensed medicine. Two tablets in 200 ml give sodium 277 mg, potassium 193 mg, chloride 352 mg and glucose 3.27 g; the brand lists it as vegan and gluten-free.
Where it wins: clinical-strength sodium (about 60 mmol/L), only 3.4 g of sugar per 200 ml, a portable tablet format, and a price of roughly 22–33p per tablet depending on the retailer.
Where it doesn't: 200 ml per two tablets means a 24-pack makes only 2.4 litres, and the taste is a lightly flavoured salt solution rather than a treat. For sport, you'd want more volume per serving.
Precision Fuel & Hydration PH 1000
What it is: a sodium-first sports drink mix. The number in the name is the sodium per litre when mixed as directed — one 20 g sachet in 500 ml delivers 1,000 mg per litre — and the range also comes in PH 500 and PH 1500 strengths so heavier sweaters can go stronger. Each sachet carries 17 g of carbohydrate, 16 g of it sugar. Around £10.99 for eight sachets.
Where it wins: the only sports product here that lets you match the sodium to how salty your sweat is, which matters: sweat sodium concentration varies a great deal between individuals and with heat acclimatisation and intensity (Baker, 2017). For long, hot sessions and ultra-distance events, this is the most sensible design on the list.
Where it doesn't: 16 g of sugar per sachet is fine during a long ride and a lot the morning after. It's also one of the pricier options and rarely stocked in supermarkets.
SiS GO Electrolyte
What it is: a carbohydrate-and-electrolyte powder from the British sports nutrition brand. A 40 g serving in 500 ml gives 36 g of carbohydrate (6.7 g sugars), 200 mg sodium, 60 mg potassium and 5 mg magnesium — about 146 kcal. Around £16 for a 500 g tub of roughly 12 servings.
Where it wins: if what you need is fuel for an hour-plus session, this does both jobs in one bottle at around 7% carbohydrate, with a sensible amount of sodium for a sports drink.
Where it doesn't: it's a fuel drink, not a rehydration drink. 400 mg of sodium per litre is a long way below the pharmacy products, and 36 g of carbohydrate is a meal's worth if you're not exercising.
High5 ZERO
What it is: a sugar-free effervescent tablet. One 4 g tablet in 750 ml gives 250 mg sodium, 70 mg potassium, 56 mg magnesium, 9 mg calcium and 28 mg vitamin C, with zero sugar; the brand notes trace caffeine (under 2 mg) from green tea extract. £6–£7.99 for 20 tablets, so 30–40p a serving.
Where it wins: the cheapest serving among the prices we checked, no sugar, a decent 56 mg of magnesium, and 750 ml of pleasant-tasting fluid per tablet — ideal for the gym bag, a hot office or a long flight.
Where it doesn't: 250 mg across 750 ml is only about 14 mmol/L of sodium. It's a drink for keeping topped up, not for getting a lot of fluid to stay in you after a bug or a very sweaty session.
Humans Against
What it is: our own recovery sachet, and a different proposition from the rest of the list. One 9 g sachet in 200 ml contains sodium chloride 200 mg (about 79 mg of sodium), glucose 3 g and citric acid 130 mg, which together help in the replacement of lost water and body salt; magnesium 200 mg (53% NRV), which contributes to electrolyte balance, normal muscle function and the reduction of tiredness and fatigue; vitamin C 500 mg and a full B-vitamin complex, which contribute to normal energy-yielding metabolism and the reduction of tiredness and fatigue; and 100 mg of caffeine, about the same as a cup of coffee — the maximum recommended intake is 400 mg a day from all sources. There are 24 active ingredients in total. It's vegan, pharmacist-formulated and made in the UK in MHRA-approved facilities. £12.95 for a box of four, so about £3.24 a sachet.
Where it wins: if your problem is the morning after rather than a marathon, the things you want from a sachet are low sugar, magnesium and the vitamins that carry the tiredness-and-fatigue claims, plus a sodium-and-glucose pairing on the ORS principle at a gentle level. That's what this is. It also carries the largest dose of magnesium on the list and the only full vitamin set. You can read the ingredient-by-ingredient detail on the science page.
Where it doesn't: be clear about what it isn't. At about 17 mmol/L it has nowhere near the sodium of a pharmacy ORS, so if you've been vomiting or have diarrhoea, buy Dioralyte or O.R.S instead. It is the most expensive serving on the list. And, because it contains caffeine, it's not suitable for under-18s or for women who are pregnant or breastfeeding; if you have a medical condition or take prescribed medication, check with your doctor before use. Follow the pack: one or two sachets in 200 ml of cold water, no more than two a day.
Lucozade Sport
What it is: the ready-to-drink sports drink you'll find in every corner shop. Retailer listings for the current Orange recipe give 50 mg of sodium per 100 ml (so about 250 mg per 500 ml bottle), with glucose syrup, sodium citrate and the sweeteners aspartame and acesulfame K, coloured with beta-carotene. The sugar figure has changed with reformulations over the years, so check the bottle. £1.65–£1.85 for 500 ml.
Where it wins: availability and convenience. Cold, in a bottle, no mixing, anywhere in the country.
Where it doesn't: about 22 mmol/L of sodium — below the level that kept fluid in volunteers in the rehydration studies — and you're paying for the water. As a drink on a hot touchline it's fine; as a rehydration product it carries far less sodium per litre than the pharmacy salts or PH 1000, though a little more than High5 ZERO or our own sachet.
Vita Coco coconut water
What it is: 100% coconut water. The brand's nutrition facts for a 330 ml carton list 65 mg sodium, 530 mg potassium and 17 g sugar.
Where it wins: taste, naturalness and potassium. In a small crossover trial in trained men, coconut water rehydrated as well as a carbohydrate-electrolyte sports drink and as well as plain water after an hour's treadmill run, so it isn't useless (Kalman et al., 2012).
Where it doesn't: the same trial found that participants reported more bloating and stomach upset after the coconut water. With only about 9 mmol/L of sodium and the sugar of a sports drink, it's a pleasant drink that happens to contain potassium, not a rehydration tool. Don't let the marketing tell you otherwise.
Which one for which job
No single winner, because there's no single job. This is how we'd pick, based on the labels above and the evidence on sodium.
| The job | Our pick | Runner-up | Why |
|---|---|---|---|
| Rehydrating after a stomach bug | Dioralyte | O.R.S Hydration Tablets | Both deliver around 60–65 mmol/L sodium in the clinical proportions; Dioralyte is a licensed medicine, O.R.S is the handier format. |
| Long or hot exercise (over an hour) | Precision PH 1000 / 1500 | SiS GO Electrolyte | PH lets you match sodium to your sweat; SiS adds fuel if you need carbohydrate too. |
| Everyday training and hot days | High5 ZERO | O.R.S Hydration Tablets | Cheap, sugar-free, portable, with some magnesium. O.R.S if you want more sodium per litre. |
| The morning after | Humans Against | High5 ZERO | Low sugar, 200 mg magnesium, the vitamins that contribute to the reduction of tiredness and fatigue, and caffeine. High5 if you'd rather skip the caffeine and the price. |
| Best value per serving | High5 ZERO | O.R.S Hydration Tablets | About 30–40p for 750 ml versus roughly 45–65p for 200 ml. (Dioralyte is likely competitive; we didn't confirm a price.) |
| Grab-and-go | Lucozade Sport | Vita Coco | Neither is a rehydration product, but both are cold, bottled and everywhere. |
| Vegan and low sugar | Humans Against | O.R.S Hydration Tablets | Both are vegan with little sugar; HA adds magnesium and vitamins, O.R.S adds far more sodium. |
The sugar question
Sugar in an electrolyte drink is neither good nor bad; it depends what the drink is for. A small amount of glucose alongside sodium is useful, because the gut absorbs the two together and water follows — the mechanism oral rehydration solution is built on, and why the WHO formula contains 13.5 g of glucose per litre (WHO, 2006). A sachet with 3 g of glucose in 200 ml is in that spirit: low in sugar, not sugar-free.
A sports drink's 30–40 g of carbohydrate per 500 ml is a different thing. It's fuel, and during exercise lasting over an hour it earns its place. The mismatch comes when a fuel drink is sold as hydration to people sitting at a desk, or when you reach for one the morning after a night out. Hangover severity, as it happens, doesn't track with blood glucose or with dehydration markers at all; when researchers measured them, the strongest correlates were immune-system factors (Penning et al., 2010). The honest case for a low-sugar morning is simply that you don't need the calories — we've set that out in our low-sugar hangover recovery guide.
One more thing worth knowing: alcohol's diuretic effect is real but small. A controlled trial found that a moderate dose taken as wine or spirits produced a modest increase in urine output over the first four hours and none at 24 hours, while beer was no different from alcohol-free beer (Polhuis et al., 2017). So the morning after is not a Dioralyte emergency. A glass of water, breakfast, and — if you want it — a low-sugar sachet with magnesium and vitamins is a proportionate response. We've compared plain water with electrolyte drinks for that specific situation in Electrolytes vs water: what actually helps the next day.
And whatever you're drinking, drink to thirst. In a study of Boston Marathon finishers, 13% had low blood sodium, and the risk factors were drinking so much that runners gained weight during the race and being on the course for over four hours; the type of drink made no difference (Almond et al., 2005). An electrolyte drink doesn't make overdrinking safe.
Built for the morning after, not the marathon
Humans Against is a vegan food supplement with 24 active ingredients — including electrolytes, with glucose, sodium and citric acid that help replace lost water and body salt, plus magnesium, which contributes to normal electrolyte balance, and vitamin C and B vitamins, which contribute to normal energy-yielding metabolism and the reduction of tiredness and fatigue. Pharmacist-formulated and made in the UK in MHRA-approved facilities. See the science.
Shop Recovery SachetsFrequently Asked Questions: Electrolyte Drinks
What is the best electrolyte drink in the UK?
It depends on the job. For rehydrating after a stomach bug, pharmacy oral rehydration salts such as Dioralyte or O.R.S Hydration Tablets deliver the most sodium per litre in clinical proportions. For long, hot exercise, a sodium-first sports mix such as Precision Fuel & Hydration lets you match the strength to your sweat. For everyday top-ups, a sugar-free tablet such as High5 ZERO is cheap and portable. For the morning after, a low-sugar sachet with magnesium and vitamins, such as Humans Against, suits the situation better than a fuel drink.
How much sodium should an electrolyte drink contain?
For serious rehydration, the research points to the pharmacy-salts range: post-exercise studies found that drinks at around 50–60 mmol/L sodium (roughly 1.2–1.4 g per litre) kept fluid in the body, while near-sodium-free drinks did not (Maughan & Leiper, 1995; Shirreffs et al., 1996). Most sports drinks and tablets sit at 14–43 mmol/L, which is fine for everyday use and for exercise but less effective after illness. Read the label and check whether it gives sodium or sodium chloride — they're not the same number.
Do I really need electrolytes, or is water enough?
Most of the time, water and food are enough. Electrolyte drinks earn their place when you've lost a lot of fluid and salt quickly — a stomach bug, or a long session in the heat — because sodium is what makes the water you drink stay in you. The morning after a night out, alcohol's diuretic effect is modest and short-lived (Polhuis et al., 2017), so a drink with a little sodium is a comfort rather than a necessity.
Is coconut water a good electrolyte drink?
It's a pleasant drink with plenty of potassium but very little sodium — about 65 mg per 330 ml carton — and 17 g of sugar. In a small trial it rehydrated trained men as well as a sports drink and as well as water, though with more bloating (Kalman et al., 2012). It's fine as a drink; it isn't a substitute for a proper rehydration product when sodium is what you need.
What's the difference between a sports drink and oral rehydration salts?
Oral rehydration salts are medical products with high sodium and a deliberately small amount of glucose, designed to replace what diarrhoea and vomiting take out. Sports drinks are fuel products with far more carbohydrate and much less sodium, designed to keep you going during exercise lasting over an hour. They can look similar on the shelf and do very different things.
Is Humans Against an oral rehydration solution?
No. It's a food supplement with a gentle sodium-and-glucose pairing (about 79 mg of sodium and 3 g of glucose per sachet) alongside magnesium, vitamin C, B vitamins and other actives, designed for the morning after. If you've been vomiting or have diarrhoea, buy a pharmacy ORS instead. Follow the pack: one or two sachets in 200 ml of cold water, maximum two a day; each sachet contains 100 mg of caffeine. Not suitable for under-18s or for women who are pregnant or breastfeeding.
Can you drink too much of an electrolyte drink?
You can drink too much of anything. Overdrinking during long exercise can dilute blood sodium (hyponatraemia), and in a study of Boston Marathon finishers the type of drink made no difference to the risk — the volume did (Almond et al., 2005). Drink to thirst, follow the pack limits on sachets and tablets, and remember that pharmacy salts are designed for short-term use during illness.
References
- Shirreffs SM, Taylor AJ, Leiper JB, Maughan RJ. Post-exercise rehydration in man: effects of volume consumed and drink sodium content. Med Sci Sports Exerc. 1996;28(10):1260–1271. doi:10.1097/00005768-199610000-00009
- Maughan RJ, Leiper JB. Sodium intake and post-exercise rehydration in man. Eur J Appl Physiol Occup Physiol. 1995;71(4):311–319. doi:10.1007/BF00240410
- Sawka MN, Burke LM, Eichner ER, Maughan RJ, Montain SJ, Stachenfeld NS. American College of Sports Medicine position stand: exercise and fluid replacement. Med Sci Sports Exerc. 2007;39(2):377–390. doi:10.1249/mss.0b013e31802ca597
- Baker LB. Sweating rate and sweat sodium concentration in athletes: a review of methodology and intra/interindividual variability. Sports Med. 2017;47(Suppl 1):111–128. doi:10.1007/s40279-017-0691-5
- Kalman DS, Feldman S, Krieger DR, Bloomer RJ. Comparison of coconut water and a carbohydrate-electrolyte sport drink on measures of hydration and physical performance in exercise-trained men. J Int Soc Sports Nutr. 2012;9(1):1. doi:10.1186/1550-2783-9-1
- Almond CSD, Shin AY, Fortescue EB, et al. Hyponatremia among runners in the Boston Marathon. N Engl J Med. 2005;352(15):1550–1556. doi:10.1056/NEJMoa043901
- Polhuis KCMM, Wijnen AHC, Sierksma A, Calame W, Tieland M. The diuretic action of weak and strong alcoholic beverages in elderly men: a randomized diet-controlled crossover trial. Nutrients. 2017;9(7):660. doi:10.3390/nu9070660
- Penning R, van Nuland M, Fliervoet LAL, Olivier B, Verster JC. The pathology of alcohol hangover. Curr Drug Abuse Rev. 2010;3(2):68–75. doi:10.2174/1874473711003020068
- World Health Organization. Oral rehydration salts: production of the new ORS (WHO/FCH/CAH/06.1). Geneva: WHO; 2006. who.int
- NHS. Salt in your diet. nhs.uk
- Dioralyte Blackcurrant Sachets — Summary of Product Characteristics (Phoenix Labs). electronic medicines compendium. medicines.org.uk
- Product labels and listings, read October 2026: Humans Against (humansagainst.com); O.R.S Hydration Tablets (Ocado, Boots); Precision Fuel & Hydration PH 1000 (Sigma Sports); SiS GO Electrolyte (Run and Become); High5 ZERO (Ocado, highfive.co.uk); Lucozade Sport Orange (Tesco, Morrisons); Vita Coco (brand nutrition facts).
- Department of Health and Social Care. Great Britain nutrition and health claims (NHC) register. gov.uk
The Bottom Line
Read the sodium line and ask what the drink is for. Pharmacy rehydration salts win for illness because they carry far more sodium per litre than anything else here except the strongest sports mixes. Sodium-first sports mixes win for long, hot exercise, and carbohydrate drinks earn their sugar only while you're moving. A sugar-free tablet is the cheap everyday answer. And for the morning after — a situation that calls for low sugar, magnesium and the vitamins that contribute to the reduction of tiredness and fatigue rather than a litre of salt — a recovery sachet is the right tool, as long as you know it isn't a medicine.
Right drink, right job.
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