Ultima vs Liquid I.V.: What Each Ingredient Does to Your Body

Short answer: Ultima Replenisher is a low-sodium, zero-sugar, magnesium-containing mix for daily sipping. Liquid I.V. is a high-sodium, sugar-containing mix for when you are actually losing fluid. Your pick should depend on your blood pressure and medications, how much you sweat, and whether you track sugar. This comparison covers the standard sugared Hydration Multiplier, and its amounts shift a little by flavor.

Per-serving numbers

	Ultima Replenisher	Liquid I.V. Hydration Multiplier
Sodium	55 mg (2% DV)	510–570 mg (22–25% DV)
Potassium	250 mg	370–380 mg
Magnesium	100 mg (25% DV)	None listed
Calcium	47–65 mg	None listed
Sugar	0 g sugar, 0 calories	11 g added sugar
Vitamins	Vitamin C as calcium ascorbate, plus zinc and manganese citrate	Vitamin C, B3, B5, B6, B12
Cost per serving	about $0.53	$16.99 per 10 sticks, about $1.70 Ultima Replenisher, Electrolyte Mix, Raspberry, 10.2 oz (288 g) +13

Sodium: a roughly tenfold gap

Liquid I.V. carries about nine to ten times the sodium of Ultima. If you have high blood pressure or a doctor-set sodium limit, one stick uses about a quarter of a day’s reference amount, and the listing flags people watching sodium intake, including those with high blood pressure, for caution. If you sweat heavily, or you have been told to eat more salt for lightheadedness on standing, Ultima’s 55 mg is too small to replace losses. It flavors water and does little else on the sodium front. iherb

Potassium: a benefit and a risk

Ultima’s potassium is about 4.5 times its sodium, while Liquid I.V. has more sodium than potassium. Higher potassium intake is linked with lower blood pressure, so Ultima’s ratio leans the way that research favors. The risk is for people with kidney disease or who take an ACE inhibitor, an ARB, or a potassium-sparing diuretic such as spironolactone. Extra potassium can build up in their blood, and listings for both brands carry that warning. Ultima suggests one to two servings per day, which means 250–500 mg of potassium. Ultima Replenisher, Daily Electrolyte Drink Mix, Lemonade, 20 StickPacks, 0.13 oz (3.7 g) Each +2

Magnesium and calcium: only Ultima has them

Ultima’s magnesium comes as magnesium citrate, which loosens stools at higher doses. Two servings (200 mg) is usually tolerable, but it counts against the 350 mg daily upper limit for supplemental magnesium if you also take a capsule. Calcium and magnesium bind some medicines, such as levothyroxine and certain antibiotics, so take those several hours apart. The Ultima listing itself says to consult a provider if you take medications that interact with calcium or magnesium. Trial evidence that magnesium prevents ordinary muscle cramps is weak, so don’t buy Ultima expecting your cramps to stop. iherb iherb

Sugar: Liquid I.V.’s sugar has a job

Liquid I.V.’s 11 g comes from cane sugar and dextrose, and glucose and sodium travel together across the gut wall, pulling water along. That helps when you are sweating hard or recovering from a stomach bug. At a desk it is just 11 g of fast carbohydrate, which matters if you have diabetes, eat keto, or count carbs. iherb

Ultima has no sugar, calories, or carbs and is sweetened with stevia leaf extract, which does not raise blood glucose. Liquid I.V. is also not a medical oral rehydration solution. Mixed in 16 oz, its sugar works out to about 23 g per liter, against 13.5 g per liter in the WHO formula. For real diarrhea or vomiting, a pharmacy ORS packet is the safer choice. iherb iherb

Vitamins: rarely noticeable

Liquid I.V.’s B vitamins are water-soluble, so the excess leaves in urine. You will only feel a difference if you were low, as can happen on a vegan diet (B12), with metformin use, or past age 50. Its niacin comes as niacinamide, which does not cause the flushing plain niacin can. The Ultima panels I found give no amounts for zinc or manganese, so treat those as trace. iherb

Acids and your teeth

Both mixes are acidic, and Liquid I.V. pairs citric acid with sugar. That combination is harder on enamel when sipped slowly over hours. Finish it within a short window and rinse with plain water afterward. iherb

What each costs you

At one serving a day, Ultima runs about $195 a year. Liquid I.V. at the same pace is about $620 by my arithmetic. Retail prices vary, so check current listings. verifiedsupplementdata

Which fits you

High blood pressure or a sodium limit: Ultima. If you take potassium-affecting medication, ask your pharmacist first.
Heavy sweater or long outdoor sessions: Liquid I.V., because Ultima’s sodium is too low to matter.
Diabetes, keto, or sugar tracking: Ultima.
You want magnesium or calcium: Ultima, since Liquid I.V. has neither.
Kidney disease: neither, until your doctor approves.
Vegan or gluten-free: both qualify, so this won’t decide it. Ultima is gluten free and vegan, and so is Liquid I.V. iherb shoprite

Bottom line: Pick the product whose largest ingredient matches your biggest need. Liquid I.V. is built around sodium and sugar for fluid replacement. Ultima is built around potassium and magnesium for everyday use with no sugar.