When to take your pet to the vet: emergency vs wait-and-see guide

The four-tier framework

Every symptom your pet shows falls into one of four tiers. The question is always “how urgent?”.

Tier 1, emergency (go now, or call an emergency vet): symptoms that can become fatal within hours.

Tier 2, urgent (same day or next morning): symptoms that are serious but not immediately life-threatening.

Tier 3, soon (book within the week): symptoms that are concerning but stable.

Tier 4, watch and log (track for a few days, reevaluate): symptoms that could be self-limiting or early stages of something.

If you are ever unsure between two tiers, go with the more urgent one.

This pillar links to specific symptom guides. For dogs: coughing, vomiting, diarrhea, limping, shaking, scratching ears, itching skin, not eating. For cats: vomiting, sneezing.

Tier 1, emergency: go now

Take your pet to an emergency animal hospital, or call one on the way. Do not wait for your regular vet to open.

In dogs and cats:

• Difficulty breathing, gasping, or rapid labored breathing.
• Collapse or inability to stand.
• Seizures (single seizure under 2 minutes: call emergency for guidance; multiple seizures or seizure over 5 minutes: go now).
• Severe bleeding that does not slow with pressure.
• Suspected poisoning (human medication, chocolate, grapes/raisins for dogs; lilies for cats; antifreeze; rodenticide; human food with xylitol). For US emergencies call the ASPCA Animal Poison Control Center at (888) 426-4435 (a fee may apply). In other countries, call your vet or the nearest emergency veterinary clinic.
• Suspected bloat in dogs: a distended belly, unsuccessful vomiting attempts, restlessness. Large, deep-chested breeds especially at risk.
• Trauma: hit by car, fall from height, fight with another animal.
• Signs of heatstroke: panting uncontrollably, collapse, hot to the touch, disorientation.
• Unable to urinate (especially male cats). The Cornell Feline Health Center calls urethral obstruction a true medical emergency: the time from complete obstruction until death may be less than 24 to 48 hours, so immediate treatment is essential.
• Severe or sudden eye injury or sudden blindness.
• Unresponsive or semi-conscious.
• Bloated abdomen with pale gums.

In cats specifically:

• Stretched-out posture with vocalizing and repeated trips to the litter box: possible urethral blockage.
• Sudden hind-leg paralysis: possible saddle thrombus.

Call the emergency hospital on your way. They can prepare.

Tier 2, urgent: same day or next morning

Call your regular vet today if they are open, or an emergency vet if not.

• Vomiting or diarrhea more than 2 to 3 times in 24 hours, or with blood.
• Refusing food for more than 24 hours (dog) or more than 24 hours (cat: cats are more sensitive to not eating and can develop hepatic lipidosis after 2 to 3 days of complete anorexia, especially overweight cats; calling sooner rather than later is the safest move).
• Drinking and urinating significantly more than usual.
• Lameness that appears to be severe pain, or sudden onset with no obvious reason.
• Pain signs: vocalizing when touched, guarding a body part, reluctance to move.
• Injury: a cut that may need stitches, a limp that is not improving, a torn nail, an insect sting with swelling.
• Vomiting with lethargy.
• Swollen face (possible allergic reaction).
• Coughing that is new or persistent.
• Discharge from eyes or nose that is green, yellow, or bloody.

If you are waiting for a morning appointment, keep your pet calm, quiet, and close to you. Log the symptoms with times.

Tier 3, soon: book this week

Not an emergency, but worth a scheduled visit.

• Persistent mild diarrhea (loose stools for 3+ days with otherwise normal behavior).
• Scratching or licking an area obsessively for several days.
• Slight weight loss noticed over weeks.
• Ear scratching or head shaking that continues over several days.
• Bad breath that is new or worsening (could be dental, could be systemic).
• Mild lethargy over several days.
• Changes in thirst that are noticeable but not dramatic.
• Skin lumps or bumps (not growing fast, but worth a check).
• Behavior changes that persist: increased hiding, increased clinginess, increased aggression.

Call your vet, book the next available appointment. Bring your symptom log.

Tier 4, watch and log: track, reevaluate

Could be nothing. Log for 3 to 5 days, then reevaluate.

• A single skipped meal in an otherwise normal dog.
• A single episode of vomiting or diarrhea in a pet that quickly recovers.
• A mild limp that resolves within 24 hours of rest.
• Mild itching for a day.
• Sneezing a few times.
• A single episode of loose stool after a food change.

When to escalate: any of these symptoms persisting beyond 3 to 5 days, worsening, or combined with lethargy or inappetence. Then move to Tier 3 or higher.

Common symptoms and what they usually mean

Not eating

In dogs: often stress, mild GI upset, or behavioral. Skipping one meal is rarely alarming. Skipping two meals or 24 hours: Tier 2. See our dog not eating guide for the full decision tree.

In cats: always more serious. Cats who refuse food for 24+ hours warrant a vet call; complete anorexia for 2 to 3 days can trigger hepatic lipidosis (fatty liver disease), especially in overweight cats. See Cornell Feline Health Center and Merck Veterinary Manual. Not eating plus hiding: Tier 2.

Vomiting

Once, then normal: probably nothing (ate too fast, grass, hairball). Multiple times in 24 hours: Tier 2. With blood, lethargy, or refusal to eat: Tier 2 or Tier 1. Projectile or with bloated abdomen: Tier 1, possible obstruction or bloat.

Diarrhea

Mild, one or two loose stools, otherwise normal: Tier 4. Persistent 3+ days or with vomiting, lethargy, blood: Tier 2. Watery, explosive, bloody, or foul-smelling: Tier 2 urgent.

Limping

Mild, intermittent, resolves with rest: Tier 4. Persistent or worsening over 24 hours: Tier 3. Non-weight-bearing (will not put any weight on the leg): Tier 2. Sudden severe pain with vocalizing: Tier 1.

Lethargy

A quieter-than-usual afternoon: Tier 4. Distinctly low energy for 24+ hours: Tier 2 or Tier 3 depending on severity. Lethargy plus not eating plus vomiting: Tier 2, possibly Tier 1.

Behavior changes

Gradual shifts over weeks: Tier 3, often reveals chronic conditions (kidney, thyroid, dental pain). Sudden aggression or severe anxiety: Tier 3, could be pain-related.

Scratching or licking

Occasional, resolved in a day: Tier 4. Obsessive focus on one area for days: Tier 3. Self-trauma (hot spots, broken skin): Tier 2.

Breed-specific red flags

Some symptoms matter more in certain breeds. If you have any of the following, know the pattern.

• Deep-chested dogs (Great Dane, Weimaraner, Standard Poodle, German Shepherd, Boxer, Doberman, Saint Bernard, Irish Setter): bloat risk is elevated. A distended, tight belly with unsuccessful vomiting is a Tier 1 emergency. The ACVS gastric dilatation-volvulus reference covers prevention (prophylactic gastropexy reduces mortality dramatically) and early recognition.
• Brachycephalic breeds (Bulldog, Pug, French Bulldog, Boston Terrier, Boxer, Persian cats): breathing problems escalate fast, especially in heat. Any sustained labored breathing is Tier 1. The University of Cambridge BOAS research programme studies breathing problems in these breeds, and the Royal Veterinary College heatstroke fact file lists flat-faced breeds among the pets at higher risk of heatstroke.
• Large-breed puppies (Labrador, Golden, German Shepherd, Great Dane, etc.): limping that persists may indicate panosteitis or growth plate issues. Tier 3.
• Male cats: urethral blockages are a Tier 1 emergency. Straining in the litter box with little output needs immediate vet attention.
• Certain cat breeds (Maine Coon, Ragdoll): elevated risk of hypertrophic cardiomyopathy. Breathing changes, sudden lethargy, or hind-leg weakness are red flags.
• Dachshunds and other long-backed breeds: sudden back pain or hind-leg weakness can indicate IVDD. Tier 1 or Tier 2.

How to describe symptoms to your vet

What you say shapes the care. Good descriptions save time and improve diagnosis.

Be specific about time: “He stopped eating Tuesday evening” beats “He has been off for a while.”

Quantify: “Vomited 4 times since noon” beats “He has been vomiting a lot.”

Note changes from normal: “Normally eats 2 cups, ate less than 1 cup today.” Your vet does not know what your pet’s normal looks like.

Log photos and videos: a 10-second video of an unusual behavior or stool sample photo is often more useful than description.

Include what you have tried: “Withheld food 12 hours, offered bland chicken and rice, vomited again after eating” gives a timeline.

Mention context: “New food brand 3 days ago” or “Visited friend’s house with other dogs yesterday” can be the key to diagnosis.

Tracking tools and what to bring

A daily 30-second log of how your pet is doing catches changes early. Appetite, energy, stools, unusual events, medications given. Paper works. Notes app works.

When you go to the vet, bring:

• Your symptom log (with dates and times).
• Any photos or videos of unusual behavior.
• A list of current medications and doses.
• Recent food changes.
• Your pet’s records (vaccines, past conditions, spay/neuter status).

For scheduled vet visits, also see our puppy first vet visit checklist or kitten first vet visit checklist with the questions to ask and paperwork to bring, and our pet records guide for organizing everything before the visit.

How Flok does it

Full disclosure: we make a pet care app.

In Flok, you can write symptom notes in your own words, with a photo, and Flok’s weekly check-in, about a minute once a week, builds a timeline you can show your vet. One PDF when someone asks for the records.

Scan with your iPhone camera to get Flok.