What Symptoms Should Never Be Ignored?

Some symptoms in dogs mean go now — not tomorrow, not after breakfast. The clearest ones are: trying to vomit without bringing anything up (especially with a swollen belly), difficulty breathing, collapse or sudden weakness, pale or white gums, a seizure lasting more than five minutes or more than one seizure in a day, straining to urinate without producing urine, a suddenly red, cloudy, or painful eye, uncontrolled bleeding, sudden inability to use the back legs, suspected poisoning, and signs of overheating.

A second group of symptoms are not emergencies but should never be watched indefinitely: a new lump, a limp that keeps returning, unexplained weight loss, a sudden increase in drinking and urinating, a sore that will not heal, a persistent cough, or a lasting change in energy or appetite. These do not require a midnight drive, but they do require an appointment rather than a wait-and-see approach.

The single most useful question to ask yourself is not "how bad does this look?" It is "is this new, is it getting worse, and does it keep coming back?" Dogs conceal discomfort well, so the severity of what you can see is a poor guide to the severity of what is happening.

Key points

• Unproductive retching with a distended abdomen is one of the most time-critical emergencies in dogs. Bloat with stomach twisting (GDV) can progress to shock within hours.
• Pale or white gums are always significant. They suggest blood loss, shock, or severe anemia, and they warrant emergency care even in a dog that seems otherwise alert.
• A seizure lasting more than five minutes is an emergency, as are two or more seizures without full recovery in between, and any first-ever seizure.
• Heatstroke first aid has changed. Current veterinary guidance is cool first, transport second, using cold water — the older advice to use only tepid water is not supported by evidence.
• Never induce vomiting at home unless a veterinarian or poison control specifically tells you to. With some substances it causes serious additional harm.
• A dog straining in the litter of the yard and producing nothing may be obstructed, not constipated. Inability to urinate becomes life-threatening within a day or two.
• A sudden red, cloudy, or painful eye can cost vision within hours. Eye pain is one of the most under-recognized emergencies in dogs.
• "He seems fine now" after collapse does not mean the crisis has passed. Internal bleeding and heat injury both produce apparent recovery followed by deterioration.

Detailed explanation

Why dogs are so hard to read

Dogs evolved to conceal vulnerability, and most will continue eating, greeting you, and wagging through a surprising amount of pain. What you tend to see instead of obvious distress is a set of small subtractions: a slightly shorter walk, more time sleeping, a moment's hesitation before jumping onto the sofa, a little less interest in dinner.

This creates a specific trap. Owners naturally calibrate urgency to how dramatic the signs look — and in dogs, that calibration runs consistently late. Several genuinely life-threatening conditions produce an early phase in which the dog looks merely "off." Trust the pattern rather than the performance.

Emergencies: signs that mean go now

Repeated attempts to vomit with nothing coming up. This is the classic sign of gastric dilatation-volvulus, in which the stomach fills with gas and then rotates, cutting off its own blood supply. According to the Merck Veterinary Manual, the typical picture includes nonproductive retching, heavy drooling, and restlessness, with acute or progressive abdominal distension; as it progresses toward shock, the dog may show weak pulses, a rapid heart rate, pale gums, and laboured breathing.

The early signs are subtler than most people expect: pacing, an inability to settle, drooling, standing with the elbows out, repeatedly looking at the flank. Deep-chested large and giant breeds are at highest risk — Great Danes especially — but it occurs in small dogs too. This condition can go from first signs to fatal within hours, and it requires surgery. There is nothing useful to do at home. Drive.

Difficulty breathing. Laboured breathing, breathing with the elbows held away from the body, open-mouthed breathing at rest, stretching the neck out to breathe, or gums that look blue, grey, or unusually pale. A dog that will not lie down, or that can only rest sitting up with its head extended, is telling you it cannot breathe comfortably lying flat. Do not put a struggling dog in a carrier if you can avoid it; keep the car cool and quiet and go.

Collapse, or sudden weakness that resolves. A dog that briefly wobbles, goes down, and then gets back up has not necessarily recovered. Episodic weakness is a recognized pattern of internal bleeding — a mass on the spleen, for example, can bleed intermittently, producing episodes of weakness that pass as the body compensates, until one bleed does not stop. Cardiac arrhythmias produce a similar picture. Either way, the episode itself is the signal.

Pale, white, grey, or blue gums. Lift the lip and look at the gum above a canine tooth. Healthy gums are pink and moist. Pale gums suggest blood loss, shock, or severe anemia; blue or grey gums suggest inadequate oxygen. Both are emergencies. It helps enormously to have looked at your dog's normal gum colour when they are healthy, so you have a baseline for comparison.

Seizures. The veterinary consensus threshold is clear and worth memorizing. A seizure lasting more than five minutes constitutes status epilepticus and requires emergency intervention. So do two or more seizures without the dog fully regaining consciousness in between. Multiple seizures in a 24-hour period — cluster seizures — also warrant prompt care even when each individual event is brief, because prolonged or repeated seizure activity drives body temperature to dangerous levels and increases the risk of escalation.

Any first-ever seizure should be evaluated, even if it is short and the dog seems normal afterward.

During a seizure: keep your hands away from the mouth, move furniture and hazards out of the way, dim the lights, note the time it started, and film it if you can. Video is genuinely useful diagnostic information.

Suspected poisoning. If your dog has eaten something questionable — human medication, sugar-free gum or candy containing xylitol, grapes or raisins, rodent bait, antifreeze, marijuana, a household chemical, or an unknown plant — call immediately. Do not wait for symptoms, because with many toxins the window in which treatment is most effective closes before signs appear.

Two 24-hour services in the United States are staffed by veterinary toxicologists:

• ASPCA Animal Poison Control Center: (888) 426-4435
• Pet Poison Helpline: (855) 764-7661

A consultation fee applies to both. Both will give you a case number that your veterinarian can use to coordinate treatment. Human poison control lines are not equipped for animal toxicology.

Critically: do not induce vomiting at home unless you are specifically told to. Home remedies circulate widely for this, and with corrosive substances, petroleum products, or a dog that is already weak or seizing, inducing vomiting causes serious additional injury. Let the toxicologist on the phone make that call.

Signs of overheating. Frantic or noisy panting, bright red gums, heavy drooling, wobbliness, vomiting, or collapse, particularly after exercise or time in a hot environment. Normal canine body temperature runs roughly 100.5–102.5°F. Heatstroke is generally considered to begin around 104–105°F, and damage escalates sharply above that.

The first aid advice here has changed, and much of what is online is out of date. The current recommendation, reflected in emergency and critical care guidance and reinforced by recent UK veterinary research, is "cool first, transport second" — begin cooling immediately, before and during the drive, rather than delaying cooling until you arrive. Cold water immersion or dousing with cold water plus air movement are the recommended methods. The long-standing warning to use only tepid water, on the grounds that cold water causes blood vessels to constrict and trap heat, has been examined and is not supported by the evidence; it persists on many websites regardless.

Practically: get the dog wet with cold water — a hose, a tub, a bucket, whatever is available — concentrate on the belly, armpits, groin, and paws, get air moving over them with a fan or open car windows, and drive with the air conditioning on. Do not skip the clinic even if your dog seems to bounce back. Heat injury damages kidneys and clotting function, and that damage can declare itself many hours later.

Straining to urinate with nothing coming out. This is frequently mistaken for constipation, because the posture looks similar. A dog that repeatedly postures, strains, and produces only a few drops or nothing at all may have a urinary obstruction. This is an emergency that becomes life-threatening within roughly 24–48 hours as toxins accumulate and the bladder distends. Frequent small amounts of urine, blood in the urine, or crying while urinating all warrant same-day evaluation.

A suddenly red, cloudy, or painful eye, or sudden vision loss. Eye pain is easy to under-rate because dogs express it quietly — squinting, tearing, pawing at the face, becoming head-shy, or simply withdrawing. Acute glaucoma is the reason this belongs on the emergency list: pressure inside the eye rises, and retinal and optic nerve damage can begin within hours, with vision sometimes lost permanently within a day. Watch for an eye that looks larger or bulging, a bluish or cloudy cornea, intense redness, a pupil that is dilated compared with the other side, or a dog bumping into things.

There are other causes of a red, sore eye that are less urgent, but you cannot distinguish them at home, and the cost of guessing wrong is permanent blindness in that eye.

Uncontrolled bleeding, or any significant trauma. Apply firm pressure with a clean cloth and go. After being hit by a car, falling from a height, or being attacked by a larger dog, a dog should be examined even if it seems unharmed — internal bleeding, diaphragmatic tears, and lung bruising are common and are not visible from the outside.

Sudden inability to use the back legs, or evident spinal pain. Dragging the hind limbs, wobbliness that appears abruptly, a hunched posture, crying when picked up, or reluctance to move the neck. Intervertebral disc disease is time-sensitive — outcomes are meaningfully better with early intervention. Keep the dog as still as possible and support the body when lifting.

Difficulty giving birth. Strong contractions for 30 minutes with no puppy, more than two hours between puppies, or green-black discharge before the first puppy arrives.

Evident severe pain. Crying out, trembling, refusing to move, an unwillingness to be touched, or a rigid, hunched abdomen. Dogs do not vocalize pain readily; when they do, take it at face value.

Not emergencies — but never things to simply watch

These do not require an overnight trip. They do require an appointment, because the common failure mode is not panicking too early but monitoring indefinitely.

A new lump, or a lump that has changed. Nobody — not you, not your veterinarian, not a specialist — can determine what a mass is by feeling it. A widely used rule of thumb is that a skin mass the size of a pea or larger, or one present for a month, should be sampled with a fine needle aspirate. It is quick, inexpensive, and usually needs no sedation. Having one confirmed fatty lump does not mean the next one is also benign.

A limp that keeps coming back. Particularly a limp that improves on pain medication and returns when the medication stops. That pattern reads as reassurance and is often the opposite. In a large or giant breed dog, persistent or recurring lameness warrants radiographs rather than another round of rest.

Unexplained weight loss. Weight loss without a diet change is meaningful in any adult dog. Use a scale rather than your eyes — gradual loss is nearly invisible in a dog you see daily, especially a long-coated one. Most clinics will let you use theirs.

A sudden increase in drinking and urinating. New, marked thirst is one of the more useful signs a dog can give you, because it points toward a specific and testable set of conditions — kidney disease, diabetes, Cushing's disease, uterine infection in unspayed females. It is easy to dismiss as weather or activity. It is worth a blood and urine panel.

Urinary signs that keep recurring after antibiotics. Blood in the urine or straining that improves during a course of antibiotics and returns after each course finishes is a pattern, not a stubborn infection. It warrants imaging.

A sore that will not heal within a couple of weeks, or one that heals and reopens.

A persistent cough, especially one that develops in an older dog with no exposure to other dogs, or a cough accompanied by reduced exercise tolerance.

Bad breath, drooling, or difficulty eating. Halitosis is usually dental, but "usually" is not "always," and dental disease itself is painful and worth addressing. A dog that approaches the bowl hungry and then backs away, chews on one side, or drops food is telling you something about its mouth.

Vomiting or diarrhea beyond about 24–48 hours, or any vomiting or diarrhea accompanied by lethargy, blood, or an inability to keep water down. Sooner in puppies, elderly dogs, or small breeds, which dehydrate quickly.

Changes in stool — straining, ribbon-shaped or flattened stool, or scooting that persists after the anal glands have been addressed.

A lasting change in behavior, energy, or interest. Increased hiding, new irritability, restlessness at night, confusion, staring at walls, or a dog that has simply stopped doing something it used to enjoy. "He's just getting old" is not a diagnosis. Aging is not a disease, and a real change in an old dog has a real cause — often a treatable one, such as pain, hearing or vision loss, or an endocrine condition.

How to make a good decision at 11pm

When you are not sure whether something is an emergency, three questions help more than searching symptoms online:

1. Is the dog's breathing normal? Effortful breathing moves a situation into the emergency category on its own.
2. What colour are the gums? Pale, white, grey, or blue means go.
3. Can the dog stand and walk normally? Collapse, staggering, or an inability to rise means go.

If you are still unsure, call. Emergency clinics take triage calls, and no reasonable veterinary team will think less of you for asking. The cost of an unnecessary call is a few minutes. The cost of a missed emergency is not comparable.

Two practical things worth doing before you ever need them: program your nearest 24-hour emergency veterinary hospital into your phone and know the driving route, and save both poison control numbers. Decision-making degrades sharply under stress, and a plan made calmly on an ordinary afternoon is worth a great deal at 2am.

When to contact a veterinarian

Go to an emergency veterinary hospital immediately for:

• Repeated attempts to vomit with nothing produced, especially with a swollen or hard abdomen
• Difficulty breathing, open-mouthed breathing at rest, or a neck stretched out to breathe
• Pale, white, grey, or blue gums
• Collapse or sudden weakness, even if the dog appears to recover
• A seizure lasting more than five minutes, repeated seizures, or a first-ever seizure
• Straining to urinate without producing urine
• A suddenly red, cloudy, bulging, or painful eye, or sudden vision loss
• Uncontrolled bleeding
• Sudden inability to use the back legs, or severe neck or back pain
• Known or suspected ingestion of something toxic (call poison control on the way)
• Signs of overheating — begin cooling immediately, before and during transport
• Being hit by a car, a fall from height, or an attack by another animal
• Strong contractions for 30 minutes with no puppy, or more than two hours between puppies
• Obvious severe pain — crying out, trembling, or refusing to be touched

Make an appointment within a few days for:

• Any new lump, or an existing lump that has changed
• A limp lasting more than two weeks, or one that returns whenever pain medication stops
• Weight loss without a diet change
• A noticeable increase in drinking and urinating
• Urinary signs that keep returning after antibiotics
• A sore that has not healed within two weeks
• A persistent cough, or reduced tolerance for exercise
• Bad breath, drooling, or difficulty eating
• Vomiting or diarrhea persisting beyond 24–48 hours
• Straining to defecate, or a change in stool shape
• A sustained change in energy, appetite, behavior, or interest in normal activities

Emergency numbers to save now:

• ASPCA Animal Poison Control Center: (888) 426-4435 (24/7, consultation fee applies)
• Pet Poison Helpline: (855) 764-7661 (24/7, consultation fee applies)
• Your nearest 24-hour emergency veterinary hospital

Questions to ask your veterinarian

• Given my dog's breed, age, and history, which specific emergencies should I be most alert to?
• What does my dog's normal look like — resting breathing rate, gum colour, body condition — so I have a baseline to compare against?
• Is my dog at risk for bloat, and would you recommend a preventive gastropexy?
• Where should I go after hours, and does that hospital have a surgeon on site overnight?
• If my dog eats something questionable, should I call you first or poison control first?
• Are there circumstances in which you would want me to induce vomiting at home, and if so, how?
• Should I keep anything specific on hand for my dog — a rescue medication for seizures, for example?
• My dog has been slowing down. Is that consistent with normal aging, or should we investigate?
• What would you want me to do differently the next time this happens?
• Can you show me how to check gum colour and capillary refill before I need to?

Sources

American Animal Hospital Association. (2025). Signs of cancer in dogs and cats: When to see your veterinarian. https://www.aaha.org/resources/does-my-pet-have-cancer-signs-of-cancer-in-pets/

American Kennel Club Canine Health Foundation. (n.d.). Heat stroke and heat exhaustion in dogs. https://www.akcchf.org/disease-history/heat-stroke-and-heat-exhaustion/

ASPCA. (n.d.). ASPCA Animal Poison Control Center. Retrieved August 4, 2026, from https://www.aspca.org/pet-care/aspca-poison-control

Charalambous, M., et al. (2024). ACVIM consensus statement on the management of status epilepticus and cluster seizures in dogs and cats. Journal of Veterinary Internal Medicine. https://doi.org/10.1111/jvim.16928

Cornell University College of Veterinary Medicine, Riney Canine Health Center. (n.d.). Heatstroke: A medical emergency. https://www.vet.cornell.edu/departments-centers-and-institutes/riney-canine-health-center/canine-health-information/heatstroke-medical-emergency

Cornell University College of Veterinary Medicine, Riney Canine Health Center. (n.d.). Managing seizures. https://www.vet.cornell.edu/departments-centers-and-institutes/riney-canine-health-center/canine-health-topics/managing-seizures

Clinician's Brief. (2021). Gastric dilatation-volvulus in dogs: Diagnosis and treatment. https://www.cliniciansbrief.com/article/gastric-dilatation-volvulus-dogs

MedVet. (2026). Gastric dilatation-volvulus (GDV) in dogs: A life-threatening emergency. https://www.medvet.com/gastric-dilatation-volvulus-gdv-in-dogs/

Merck Veterinary Manual. (2025). Gastric dilation and volvulus in small animals. https://www.merckvetmanual.com/digestive-system/surgical-problems-of-the-gastrointestinal-tract-in-small-animals/gastric-dilation-and-volvulus-in-small-animals

Merck Veterinary Manual. (2024). Glaucoma in dogs. https://www.merckvetmanual.com/dog-owners/eye-disorders-of-dogs/glaucoma-in-dogs

North Carolina State University Veterinary Hospital. (n.d.). What are common warning signs of cancer in pets? https://hospital.cvm.ncsu.edu/resources/animal-care/what-are-common-warning-signs-of-cancer-in-pets/

Royal Veterinary College. (n.d.). The RVC urges owners of hot dogs to "cool first, transport second." VetCompass. https://www.rvc.ac.uk/vetcompass/news/the-rvc-urges-owners-of-hot-dogs-to-cool-first-transport-second

UK Vet Companion Animal. (2023). Canine heat-related illness — New perspectives from recent research. https://www.ukvetcompanionanimal.com/content/clinical/canine-heat-related-illness-new-perspectives-from-recent-research

Veterinary Vision Animal Eye Specialists. (n.d.). Emergency treatment for glaucoma. https://www.veterinaryvision.com/emergency-treatment-for-glaucoma

This article is for educational purposes only and is not a substitute for veterinary care. It cannot diagnose any condition in your dog. If you are concerned about your dog's health, contact your veterinarian. If your dog is showing signs of collapse, difficulty breathing, pale gums, uncontrolled bleeding, seizures, or suspected poisoning, seek emergency veterinary care immediately.