Underdog Hydration

Field-tested hydration

Water that keeps up on the trail — and back.

A working electrolyte for dogs who actually move. No sugar. No dye. No filler. Just the salts a running dog burns and the water she drinks to replace them.

See the pack How we field-test

The pack — 3 formulas

One recipe. Three flavors dogs will actually drink.

Trailhound Lime Post-hike electrolytes
Fetch Fuel Berry Training-day recovery
Cool Down Coconut Hot-day cool-off

Field notes — Boulder, October

"A dog on a hot trail loses electrolytes the same way you do — she just can't ask for a Gatorade." — Dr. R. Halden, DVM · formulation partner

  1. 01 — Formulation

    Vet-balanced, not human-scaled-down.

    Human sports drinks skew heavy on sugar and light on the salts a panting dog actually loses. We rebuilt the ratio from the dog side — closer to a working-dog IV drip than a Gatorade.

  2. 02 — Ingredients

    Zero sugar, zero dye, zero xylitol.

    The three things a dog should never drink. That's the whole list. Everything on the label is either an electrolyte, water, or a natural flavor a dog will accept warm out of a bowl at mile eight.

  3. 03 — Testing

    Field-tested with real trail dogs.

    Every batch is trialed with our test pack of Boulder trail dogs before it ships. If the dogs don't drink it, it doesn't leave the kitchen.