When the temperature rises, it’s not just humans who lose their appetite — dogs can too. A dog not eating in hot weather can leave any pet parent feeling uneasy, especially when your pup seems otherwise normal but refuses their favorite meal.
We outline the common reasons why dogs may not eat in hot weather, what you can do at home, and when to seek veterinary help.
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Dog Not Eating in Hot Weather — Why It Happens
A dog refusing food in hot weather is often experiencing the same effects heat has on us — reduced appetite, dehydration, or discomfort from overheating. High temperatures can cause dogs to feel sluggish, tired, and less interested in food. In some cases, it’s a normal seasonal adjustment, but it can also point to heat exhaustion, dehydration, or underlying illness. Dogs rely on panting to cool themselves, and when that system is overwhelmed, they can lose energy fast and skip meals to conserve it.
Dog Not Eating in Hot Weather: Common Causes
1. Heat Exhaustion
When the body temperature rises beyond normal, dogs can develop heat exhaustion — a dangerous condition that can quickly progress to heatstroke.
Excessive heat causes panting, drooling, weakness, and loss of appetite. Your dog may also vomit, have diarrhea, or appear dazed. Skipping meals during extreme heat is the body’s way of reducing internal heat production and energy use.
If not managed, heat exhaustion can become life-threatening, so always treat it as a warning sign.
Read more: Dog Not Eating No Other Symptoms (What it means and what to do)
2. Dehydration
In hot weather, dogs lose moisture through panting and need far more water than usual. Dehydration makes them feel lethargic, weak, and nauseated — all of which suppress appetite.
If your dog’s gums are dry or sticky, or if their skin takes a moment to fall back when gently pinched, dehydration could be the culprit.
A dehydrated dog will often refuse food, especially dry kibble, since eating can worsen the discomfort in the mouth and throat.
Ensure constant access to cool, clean water and shaded rest areas.
3. Normal Summer Appetite Changes
Just as people eat less during hot days, dogs naturally reduce calorie intake when temperatures soar. Their bodies don’t need as much energy to stay warm, so appetite may temporarily decrease.
This is usually harmless if your dog is still playful, hydrated, and maintains a healthy weight. However, if the appetite loss lasts more than 24–48 hours, monitor closely — prolonged refusal could signal a deeper issue masked by heat.
4. Gastrointestinal Upset
Hot weather can accelerate food spoilage, especially if wet food, meat, or leftovers are left out too long. Eating spoiled food or drinking from contaminated water sources can irritate the stomach and intestines, leading to nausea and refusal to eat.
You might also notice vomiting, diarrhea, or drooling. This cause often improves once the upset passes — but keep an eye out for persistent symptoms that suggest infection or toxins.
5. Stress or Environmental Changes
Summer often brings changes — travel, fireworks, loud outdoor events, or even visiting guests. Dogs sensitive to disruption may stop eating when stressed.
Anxiety suppresses appetite through hormonal shifts, and a dog’s body may respond with mild digestive upset or restlessness. Keep routines predictable and feeding areas quiet to help your dog relax during hot, hectic months.
6. Underlying Health Issues Triggered by Heat
Sometimes, hot weather exposes health problems that weren’t noticeable before. Conditions like heart disease, respiratory issues, or thyroid disorders can make dogs more sensitive to heat and reduce appetite.
For instance, dogs with short muzzles (like Pugs, Bulldogs, and Boxers) often struggle to breathe efficiently in hot weather and tire easily — leading to skipped meals. Similarly, older dogs or those on medication may have reduced thirst or appetite when overheated.
Always consider an underlying issue if your dog’s lack of appetite persists despite cooling and hydration.
Read more: Old dog not eating (When to worry)
What to Do
If your dog won’t eat during hot weather, first make sure they’re cool, calm, and hydrated. Move them to a shaded or air-conditioned space and offer cool (not ice-cold) water frequently.
Encourage eating by offering lighter meals — such as wet food or broth-soaked kibble — which are easier to digest and help increase fluid intake. Avoid leaving food out too long, especially outdoors, since it can spoil quickly and deter your dog from eating.
If your dog is panting heavily, seems tired, or refuses food for more than 24 hours, you can try tempting them with mild, vet-approved options like boiled chicken and rice. However, never force-feed or push food if your dog seems ill — that can worsen nausea.
Keep daily walks shorter and avoid exercise during peak heat. Feeding in the cooler hours (early morning or evening) can also help stimulate appetite when the environment feels more comfortable.
If your dog’s behavior changes drastically — for instance, they’re vomiting, weak, or avoiding water — it’s time to call the vet right away.
When to Visit Your Vet
You should contact your veterinarian if your dog:
Hasn’t eaten for more than 24–36 hours, even after cooling off.
Shows signs of dehydration (dry gums, sunken eyes, sticky saliva).
Is vomiting or has diarrhea in addition to not eating.
Seems weak, confused, or collapses.
Pants excessively or struggles to breathe.
Has a body temperature over 104°F (40°C).
These can all indicate heatstroke or a medical condition worsened by heat — both require urgent care.
Your vet can perform tests to rule out organ stress, infection, or metabolic disorders, and provide IV fluids or cooling support if needed.
Read more: Dog Not Eating Due to Stress (Possible causes and treatments)
Key Takeaway
Hot weather can easily suppress your dog’s appetite, but it can also mask more serious conditions like heat exhaustion or dehydration.
If your dog isn’t eating, first make sure they’re cool and hydrated — but never ignore other symptoms like vomiting, lethargy, or breathing trouble.
When in doubt, always call your vet. Quick action during hot spells can prevent life-threatening complications and keep your dog safe, comfortable, and well-fed all summer long.