Dogs can’t tell us when something hurts. They can’t point to a sore leg or explain that their stomach aches. Instead, they talk to us through behavior — the way they move, eat, sleep, and play. Learning to read these quiet signals is one of the most loving things you can do as a dog owner.
This guide walks through the most common signs that your dog might be sick or in pain. It doesn’t replace a veterinarian’s advice, but knowing what to watch for helps you catch problems early — and early action often makes all the difference.
Behavior Changes: Your First Clue
Dogs are creatures of habit. A dog that normally greets you at the door and suddenly stays on his bed is telling you something. Behavior changes are often the very first sign that something is wrong, sometimes before any physical symptom appears.
Watch for a dog that becomes unusually quiet, withdrawn, or less interested in things he used to love. Some dogs become clingy and follow their owner everywhere, while others hide in corners or under furniture. Both reactions can be a sign that your dog is trying to cope with feeling unwell.
Sleep changes matter too. A sick dog often sleeps much more than usual, while a dog in pain may pace and struggle to settle. You know your dog’s normal better than anyone.
Changes in Appetite and Drinking
A sudden loss of appetite is one of the most common signs that a dog is sick or in pain. If your dog turns away from food he normally enjoys — or skips meals for more than a day — take it seriously, especially with low energy or vomiting.
Watch for other eating-related signs. A dog that drops food from his mouth, chews on one side, or cries while eating may have mouth or tooth pain. Excessive drooling that is new and unusual for your dog can point to mouth pain, nausea, or other problems.
Drinking habits matter as well. Drinking much more or much less than usual can both be warning signs. A noticeable change in either direction for more than a day or two is a good reason to call your vet.
Posture and Body Language Signals
A dog’s posture can reveal pain that words never could. Dogs in pain often hunch their back, tuck their belly tightly, or stand with their head low. The classic “prayer position” — front end down, back end up — can be a sign of stomach pain and should be taken seriously.
Look at your dog’s face. Dogs in pain may squint, flatten their ears back, or wear a tense, worried expression. Frequent lip-licking or yawning when not tired can also signal stress or discomfort — small signals, but they add up.
Notice how your dog moves around the house. A dog that used to jump on the couch but now hesitates may have joint or back pain. If your dog flinches when you touch a certain spot, don’t push it — that reaction is information worth sharing with your vet.
Limping, Stiffness, and Trouble Moving
Limping is one of the most obvious signs that something hurts. Sometimes the cause is simple, like a thorn in the paw or a small cut. Other times it may point to a sprain, joint problem, or something deeper that needs a vet’s examination.
If you notice limping, check your dog’s paws — look between the toes for anything stuck, and check for swelling, cuts, or a broken nail. But if there’s no visible injury and the limp lasts more than a day, or if your dog refuses to put weight on the leg at all, call the vet. A dog that won’t bear weight on a leg could have a fracture or serious soft-tissue injury.
Stiffness is another movement sign, especially in older dogs. A dog that is stiff when getting up after a nap but loosens up after moving may be dealing with arthritis — very common in senior dogs. Don’t just assume stiffness is “old age.” There are safe, vet-approved ways to help arthritic dogs feel more comfortable, but they start with a proper diagnosis.
Panting, Breathing, and Vocal Signs
Panting is normal after exercise or on a hot day, but heavy panting when your dog is resting in a cool room can signal pain, stress, or illness. Dogs in pain often pant in a shallow, rapid way that looks different from happy post-exercise panting. If it doesn’t stop after rest and water, treat it as a signal worth investigating.
Watch for labored breathing, where the belly moves a lot with each breath, or new wheezing. Any real trouble breathing should be treated as urgent — dogs can get into serious trouble quickly when they can’t breathe well.
Dogs also “talk” about pain with sounds. Whining, whimpering, or groaning — especially when touched or moving — are direct signals of discomfort. A normally vocal dog that suddenly goes silent may also be unwell.
Digestive Signs: Vomiting, Diarrhea, and More
A single episode of vomiting or soft stool after eating something unusual often passes on its own. But repeated vomiting, ongoing diarrhea, or digestive problems lasting more than a day are signs your dog may need veterinary care.
Note the details — they help your vet figure out what’s going on. Is the vomit mostly food or liquid? Is the diarrhea watery or an unusual color? Is your dog still drinking water and keeping it down? Jot these down before you call; it saves time.
Other warning signs include a swollen or hard belly, straining to poop with nothing coming out, or dry heaving without bringing anything up. Dry heaving — especially in large, deep-chested breeds — can be a sign of a dangerous emergency called bloat, which needs immediate care. Blood in vomit or stool also means a prompt vet visit.
Skin, Coat, and Eye Changes
Your dog’s skin and coat reflect his overall health. Excessive scratching, red or inflamed skin, bald patches, flaky skin, or a coat that suddenly turns dull can be signs of allergies, infections, parasites, or other possible health issues.
New lumps and bumps deserve attention. Many turn out harmless, but any lump that grows quickly, changes shape, or feels painful should be checked by a vet. Don’t squeeze or treat lumps at home.
Eyes and nose give clues too. Red, cloudy, or swollen eyes, heavy discharge, or constant pawing at the face may mean an eye problem needing treatment. Bad breath that is much worse than usual can point to dental problems — dental pain is common in dogs and often goes unnoticed.
Changes in Bathroom Habits
Straining to urinate, peeing very small amounts very often, or crying while peeing can be signs of a possible urinary problem. Blood in the urine is always a reason to call the vet. A dog that suddenly starts having accidents indoors after being fully house-trained may be sick rather than misbehaving.
A dog that stops peeing or can’t pee at all is an emergency — this can quickly become life-threatening, especially in male dogs. Don’t wait to see if it improves. The same urgency applies to straining to poop with nothing coming out.
Also watch stool changes. Very dark, tar-like stool can indicate bleeding higher in the digestive tract; bright red blood usually comes from lower down. Either way, blood in the stool means a vet visit.
Fever and Shivering
Dogs run warmer than humans — normal is roughly 101 to 102.5°F (38.3–39.2°C). You can’t reliably detect a fever by feeling the nose; the only accurate way is a pet rectal thermometer, used gently with a little petroleum jelly.
Signs that may suggest a fever include shivering when it’s not cold, warm ears and belly, glassy eyes, and appetite loss. Call your vet if the temperature is above 103°F (39.4°C), or if a lower fever lasts more than a day.
Shivering isn’t always about fever. Dogs also tremble from pain, fear, anxiety, or nausea. If your dog is shaking with no obvious reason, watch for other symptoms and call your vet if they appear.
What NOT to Do
When your dog looks sick or in pain, it’s natural to want to fix it fast. But some well-meaning actions can make things worse.
Do not diagnose your dog yourself. Searching symptoms online is a useful starting point, but only a veterinarian can examine your dog, run tests, and find the real cause. Guessing wrong can delay proper treatment. Use your observations to give your vet good information — then let them make the call.
Never give your dog human medicines. This is one of the most dangerous mistakes owners make. Common human painkillers like ibuprofen and acetaminophen (paracetamol) are toxic to dogs and can cause serious organ damage even in small amounts. Only give medicines your vet has specifically prescribed, at the exact dose they gave you.
Don’t force your dog to eat, drink, or exercise. Offer fresh water and his normal food, and let your vet guide the next steps. Don’t push a limping or tired dog to “walk it off” — rest is usually what he needs.
Don’t wait too long hoping it passes. Mild, short-lived issues often resolve on their own, but waiting days while symptoms worsen can turn a treatable problem into an emergency. When in doubt, call your vet and describe what you see.
When to See a Vet
Some signs mean “call the vet soon,” and others mean “go now.” These red flags need urgent or emergency care:
- Trouble breathing — labored, noisy, or very rapid breathing, or blue/gray gums
- Repeated vomiting or diarrhea — especially with blood, or vomiting that won’t stop
- Dry heaving without producing vomit — possible bloat, an emergency
- Can’t urinate or defecate — straining with nothing coming out
- Collapse, fainting, or extreme weakness — can’t stand or suddenly falls over
- Seizures — especially repeated ones or lasting more than a couple of minutes
- Swollen, hard, or painful belly — especially with restlessness or pacing
- Bleeding that won’t stop, deep wounds, or suspected broken bones
- Refuses to put weight on a leg or sudden inability to walk
- Not eating or drinking for more than 24 hours, especially puppies or small dogs
- Fever above 104°F (40°C) or any fever lasting more than a day
- Possible poisoning — ate chocolate, grapes, xylitol, or rat poison
For less urgent signs — a mild limp lasting more than a day, new lumps, or behavior changes without other symptoms — call your vet’s office, describe what you’ve noticed, and ask whether your dog should come in. Note when each symptom started; it helps your vet a lot.
Save your nearest emergency vet clinic’s number in your phone now, before you ever need it. A quick call can tell you whether to come in immediately or wait until morning.
Frequently Asked Questions
How can I tell if my dog is in pain?
Dogs rarely cry out unless pain is sudden or sharp. Look for quieter signals: limping or stiffness, reluctance to move or be touched, hunching, panting at rest, restlessness, appetite loss, or snapping when handled. A dog in pain may also lick or chew one spot repeatedly. If several of these appear together, your dog is likely hurting and should be checked by a vet.
Why is my dog hiding all of a sudden?
Dogs often hide when they feel sick, scared, or in pain — it’s an instinct to find a quiet spot when vulnerable. Check for other signs like appetite loss or lethargy. A hiding dog that also refuses food or seems distressed should see a vet.
What are the first signs of a sick dog?
The earliest signs are usually subtle: a little less energy, slightly less interest in food or play, or sleeping more. Many owners describe it as a gut feeling that something is off — and they’re often right. Catching these quiet changes early gives your vet the best chance to treat problems before they become serious.
My dog is shaking but it’s not cold — should I worry?
Shaking has many possible causes: pain, fever, nausea, fear, or anxiety. If shaking comes with other signs — appetite loss, vomiting, lethargy, or hiding — it’s more likely medical, and you should call your vet. When in doubt, call your vet’s office.
Can I give my dog anything for pain at home?
No — do not give any pain medicine unless your vet specifically prescribed it. Human painkillers like ibuprofen and acetaminophen are toxic to dogs. Keep your dog comfortable and rested, offer water, avoid touching sore areas, and call your vet to describe the symptoms.
A Final Word for Worried Dog Parents
Watching your dog for signs of sickness or pain isn’t about being anxious — it’s about being attentive. Most health problems are far easier to treat when caught early, and you are the person most likely to notice that first small change.
Trust what you see, keep notes when something seems off, and never feel silly about calling your vet. Your dog depends on you to be his voice — and by learning his language, you’re already doing a wonderful job.