How Long Dogs Can Go Without Water
The short answer is that dogs can survive between 48 and 72 hours without drinking, but that doesn't capture the whole picture. Survival is a minimum and a dog allowed to drink only once every 2 days would be the subject of cruel abuse.
Without enough access to fresh, clean water, their vital organs will fail and could potentially lead to death, and being dehydrated all the time leads to continual strain on dogs that will have hugely negative impacts on their quality of life.
If your dog has refused to drink any water for more than a single day, contact an emergency vet immediately.
How Much Water Dogs Should Drink
The average adult dog should be drinking an ounce of water for every pound they weigh. If you're making sure more than this amount is available to your dog, they will not be at risk of running out before they've had enough in most circumstances.
If you're worried your dog isn't consuming enough water, put out the exact number of ounces their weight would dictate they need and see if they are finishing all of their water.
Signs of Dehydration in Dogs
The following symptoms are all signs of dog dehydration:
Listlessness: If your dog is acting lethargic it may be because they feel fatigued or weak. Dehydration is a likely culprit as water is needed for proper blood circulation.
Excessive panting: Dogs pant to regulate their body temperature since they can't sweat as people do. If your dog has begun panting heavier than normal without explanation, it could mean they are suffering from dehydration.
Dry mouth and/or gums: There is no time when a healthy dog's mouth shouldn't be reasonably moist. If you detect a lack of wetness in your dog's mouth you should contact your vet.
Poor appetite: Dehydrated Dogs are more likely to turn their nose up at food, as dehydration makes chewing and swallowing difficult or even painful.
Sunken eyes: When severely dehydrated, the muscles that hold the eyes in place dry out and could make the eyes look noticeably sunken.
Inelastic skin: In a healthy dog, the skin should flatten out immediately after pinching it. If it holds its pinched shape, your dog is likely dehydrated.
Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.