How to Tell if Your Dog Is Dehydrated: Key Signs to Know

As the summer months approach, it's important to enjoy the warmer weather with your dog while remaining aware of the risks dehydration poses in hot conditions. Dogs need more water in summer to cool themselves effectively and prevent dehydration, which can quickly lead to heatstroke if untreated.

Why Might My Dog Become Dehydrated Despite Water Being Available?

Dogs feel thirst just like we do and generally drink when they need to, but dehydration can still happen for several reasons. Sometimes the water bowl may accidentally run dry, or your dog could knock it over without you noticing, especially if you are out most of the day. Additionally, thirst itself is a symptom of early dehydration; by the time a dog feels thirsty they may already be somewhat dehydrated.

In warmer weather, dogs lose more water through panting—an essential cooling mechanism—and evaporation speeds up fluid loss. Even if your dog drinks more than usual, this might not fully compensate for the increased water use. Therefore, never assume your dog is well hydrated simply because they've had a drink recently. Early dehydration can self-correct if water remains accessible and the dog can drink, but vigilance is key.

Key Signs Your Dog May Be Dehydrated

1. Seeking Water in Unusual Places

If your dog is sniffing, licking wet floors, or drinking from puddles, it’s often a clear sign they need fluids urgently. Don’t dismiss this as odd behaviour; check their water supply to ensure it’s clean, plentiful, and accessible.

2. Heavy Panting

Prolonged, intense panting helps dogs cool down but also causes water loss. It indicates they need more water to replace moisture lost from their body, especially after exercise or in warm weather.

3. Dry or Sticky Gums

Healthy dogs have moist, shiny gums with saliva. If your dog’s gums feel dry, tacky, or look dull rather than glossy, this points to dehydration. You can gently press their gums and watch colour return; slow refill is a concern and warrants attention.

4. Lethargy or Reduced Engagement

Dehydration affects a dog’s energy and mood. Sudden lethargy, disinterest in play, or lack of usual enthusiasm can signal dehydration, often alongside heat stress.

5. Sunken or Dry Eyes

Eyes should appear bright and moist. Dull, sunken eyes typically indicate advanced dehydration and require immediate veterinary care.

6. Loss of Appetite

Dogs turning down treats or food may be feeling unwell due to dehydration or underlying heat-related illness. Offering water instead is more important.

7. Reduced Skin Elasticity

Perform the skin tent test by gently pinching the loose skin between your dog’s shoulder blades or neck. Healthy skin snaps back immediately; if it returns slowly or remains tented, your dog is dehydrated. This simple test is a useful at-home check.

8. Thick, Stringy Saliva and Other Signs

Sometimes saliva becomes thick and sticky when dehydrated. Also watch for decreased urination, dark yellow urine, vomiting, or diarrhoea, which can cause or worsen dehydration.

How to Prevent and Treat Dehydration in Your Dog

Prevent dehydration by offering multiple access points to fresh, clean water inside and outside the home, especially in warmer weather. Use shaded, cool water bowls and consider ice cubes or frozen treats for encouragement. When out and about, carry water and a collapsible bowl for your dog to drink frequently.

Incorporate moisture-rich foods such as wet dog food or dog-safe fruits (like watermelon) to boost hydration. Monitor your dog's behaviour carefully during hot weather or exercise times.

If you notice signs of mild dehydration, encourage small sips of water often. If your dog is unable to keep water down, vomiting, or shows severe symptoms like sunken eyes or lethargy, seek veterinary advice promptly.

Veterinary treatment may include subcutaneous or intravenous fluids to restore hydration in moderate to severe cases. Address any underlying health conditions causing dehydration, such as illness or heatstroke, quickly to avoid long-term complications.

Regular hydration checks, like the skin tent and gum tests, help you spot dehydration early to protect your dog’s health.

Summary

Remember that dehydration in dogs can escalate rapidly and is especially risky in summer. Know these 8 key signs: seeking water unusually, heavy panting, dry gums, lethargy, sunken eyes, loss of appetite, poor skin elasticity, and thick saliva. Always keep fresh water accessible, act early, and consult your vet if in doubt.

By staying informed and proactive, you can ensure your dog stays comfortable, safe, and well hydrated year-round.