Episode 28  ·  11m 02s

What Your Pet's Behavior Is Trying to Tell You

Dr. Michael LoSasso, DVM & Julie Schwenzer Frisco Emergency Pet Care
Warning signs Lethargy Fainting Urinary emergencies Behavior changes
"When dogs are not feeling well, their behavior often tells the story long before symptoms become obvious. Today we're breaking down the subtle and not-so-subtle changes that signal something could be serious."
— Julie Schwenzer

Episode summary

This episode is a practical run-through of what different behavior changes actually mean — and which ones warrant a same-day ER visit versus a conversation with your regular vet. Dr. LoSasso starts with the basics: sudden lethargy is more concerning than sudden hyperactivity, since illness typically drops energy rather than raising it, and reduced sociability — not wanting to play, avoiding interaction — is a real signal even though it's nonspecific on its own.

On appetite, he's refreshingly calm: GI complaints are the number one reason people bring dogs to his ER, and plenty of those dogs simply skipped one evening meal. A single missed meal alone isn't cause for alarm — what raises his concern is a missed meal paired with restlessness, an inability to settle or get comfortable, or drooling, which is typically a sign of nausea (though he notes some dogs, famously Labradors, just drool from anxiety, car rides being a classic trigger).

"Excessive water consumption is an important behavioral change that can indicate a couple of things — diabetes will cause anybody to drink more water, renal disease will definitely cause anybody to drink more water... it's also associated with Cushing's syndrome."
— Dr. Michael LoSasso, DVM

Excessive thirst gets its own flag as a real diagnostic clue — tied to diabetes, kidney disease, or Cushing's syndrome. He adds a specific tell for dogs with GI discomfort: some drink a full bowl at once hoping it'll ease stomach pain, then regurgitate it because it physically doesn't fit — so water regurgitation after a big drink is itself worth mentioning to your vet.

Signs that mean go now

Fainting (a syncopal event) is, in Dr. LoSasso's words, always a trip to the ER for him — it's usually tied to heart failure or an arrhythmia interrupting effective heartbeat, and he specifically flags sick sinus syndrome in Schnauzers as a known cause. Fainting alongside a rising respiratory rate or an unusual mucous membrane color (a purple tongue, for example) needs immediate attention. And a male cat repeatedly visiting the litter box without producing urine is a true emergency — a possible urethral blockage that prevents eliminating potassium, which becomes dangerous fast. (Female cats with the same pattern are more often dealing with a urinary tract infection — still worth an exam, just typically less immediately dangerous.)

Straining to defecate, he notes, is often misread by owners as constipation when it's actually the opposite — colon irritation from diarrhea, a condition with the $20 name "tenesmus," causing straining even though there's nothing left to pass. On lumps, his advice cuts against the instinct to rush to the ER: a lump that's been slowly developing over weeks or months is usually better suited to a general practice vet who can run cytology during a planned visit, while a lump that appears suddenly — especially after hours — is a reasonable reason to come in. And on sudden aggression in a normally easygoing pet, his read is simple: it's usually a sign that something hurts. In an older dog that snaps when a younger housemate tries to play, arthritis is a common culprit, though pain anywhere in the body — or neurological changes in senior pets — can shift temperament.

Questions answered in this episode

The following questions are answered by Dr. LoSasso in this episode, drawn directly from the conversation. These are real clinical answers from a practicing emergency veterinarian with 30+ years of experience.

Not by itself. Dr. LoSasso says GI issues are the number one reason people bring dogs to his ER, and many of those dogs simply skipped one evening meal. He's not concerned about a single missed meal alone — the picture changes when it's paired with restlessness, an inability to get comfortable, drooling (a sign of nausea), or actual vomiting.
Dr. LoSasso lists several possibilities: diabetes, kidney (renal) disease, and Cushing's syndrome can all cause increased thirst. He also notes that dogs with GI discomfort sometimes drink a lot of water thinking it'll ease their stomach pain, then regurgitate it because their stomach can't hold a full bowl at once — so excessive water regurgitation after drinking is itself a clue worth mentioning to your vet.
Yes, in Dr. LoSasso's view. Fainting (a syncopal event) in dogs is usually tied to heart failure or an arrhythmia that briefly interrupts effective heartbeat, starving the brain of oxygen. He specifically flags sick sinus syndrome in Schnauzers as a common cause. Fainting paired with a rising respiratory rate or an unusual mucous membrane color — like a purple tongue — needs to be seen right away.
In a male cat, yes — Dr. LoSasso calls this a real emergency, since it likely means a urethral blockage. A cat that can't urinate can't eliminate the potassium building up in its blood, which becomes dangerous quickly. In female cats, repeated unproductive litter box trips are more often a urinary tract infection, though it still warrants an exam. He also notes that straining that looks like constipation is often actually diarrhea and colon irritation (tenesmus) rather than an actual blockage.
Not necessarily. Dr. LoSasso says a lump that's been slowly developing over weeks or months is generally better suited to a general practice vet, who can run cytology in a planned visit. A lump that appears suddenly, especially after hours, is a reasonable reason to go to the ER.
Dr. LoSasso says it's often a sign that something hurts, even if it's not an emergency in itself. In an older dog that suddenly snaps when a younger housemate tries to play, arthritis is a common culprit. Pain anywhere in the body can change a pet's attitude, and he notes that behavioral changes, including new aggression or irritability, can also stem from neurological changes, particularly in senior dogs.
JulieWhen dogs are not feeling well, their behavior often tells the story long before symptoms become obvious. If a dog's energy level suddenly changes drastically, does that indicate they need emergency care?
Dr. LoSassoPossibly — it certainly could. Any changes, even subtle ones, don't necessarily mean emergency care, but they mean something's worth checking out. If energy level suddenly drops and they're very lethargic, that's worse than being especially hyperactive — generally with sickness you see a decrease in energy. Eating is obviously a change too. Vomiting isn't a behavior, it's a clinical sign, but becoming less social, not wanting to play with other pets they'd normally play with — that's a behavioral change that can signify something's going on. Those aren't very specific signs, but they're an indication that something has changed.
JulieOne thing that usually freaks us out as pet parents is if our dog or cat stops eating. Does that warrant a trip?
Dr. LoSassoIt's worth talking about. I see lots of dogs for GI issues — it's the number one reason people come to an ER. A lot of them are dogs that just skipped one evening meal and they're right in the emergency room, which isn't a bad instinct, we're just a bit more trustworthy than some of these dogs — we don't get concerned that we've eaten mulch out of the backyard, but dogs will do it. Even missing one meal, especially with other signs of GI discomfort — can't get comfortable, moving around, restless — is worth noting, though that's not necessarily a hallmark of GI pain specifically. A lot of times if they've got gas or intestinal discomfort, they'll shift around trying to find a position that helps, not realizing there isn't one. We also watch for increased salivation — drooling is typically a sign of nausea in people and dogs, though at home it could also just be anxiety, especially in a Labrador — for some reason they drool everywhere when nervous. I had a cat that would froth every time we put her in the car. She hated it.
JulieWhat about drinking water excessively, or not drinking at all?
Dr. LoSassoExcessive water consumption is an important behavioral change that can indicate several things in dogs and cats. Diabetes will cause anybody to drink more water. Kidney disease will definitely cause more drinking. A lot of GI dogs actually drink a lot of water thinking it'll make their problem better — they also tend to regurgitate a lot of it, because they'll drink a whole bowl at once and it just doesn't fit, so some comes back up. Increased water consumption is also associated with Cushing's disease.
JulieThis might be obvious, but if they pass out, is that always a trip to the ER?
Dr. LoSassoFor me it would be. Fainting doesn't happen very often in dogs, but it does happen — we call it a syncopal event. Most of those dogs have either heart failure or an arrhythmia that stops the heart from beating effectively, and the brain, not getting oxygenated properly, essentially shuts everything off and turns it back on. We see fainting especially in Schnauzers with sick sinus syndrome, a pretty common arrhythmia in that breed, and as a general rule in smaller dogs. Usually they also have an increased respiratory rate — if you notice faster, heavier breathing over time, that's something we'd want to know about. Same with mucous membrane color — if you're thinking, "I've never seen her tongue purple," purple's not a good color, that needs to be seen.
JulieWhat about when a dog can't urinate or have a bowel movement?
Dr. LoSassoStraining to urinate or defecate is an indication they need attention. It may or may not mean there's an actual blockage — a lot of times both organs are actually empty, but pain or irritation stimulates the brain to think they need to be emptied when they don't. Urinary tract infections cause what we'd call urge incontinence in humans — female cats will constantly go to the litter box and not produce, which could indicate a UTI. In male cats, that's a very significant sign and a real emergency, because if they've got a plug in the urethra and are blocked, they can't get rid of the potassium in their urine, and that's serious. A lot of dogs come in for presumed constipation because owners see them straining in the yard, but often they actually have more diarrhea than constipation and are straining because the colon is irritated — tenesmus — not because it's actually full. Those changes definitely warrant at least a conversation and a physical exam.
JulieWhat about lumps that come on quickly and are firm — should we bypass general practice and go straight to the ER since they have the tools to look at it?
Dr. LoSassoNot necessarily. General practice is often better suited for lumps and bumps with cytology — most ERs can do that too, we just don't do it as often. Something that comes up very suddenly, that same day, is an acute problem, and if it's after hours, the ER is probably the place. But something you've noticed building up over weeks to months is probably better suited to general practice.
JulieWhat if a dog that's usually docile becomes really aggressive and upset — is that a red flag?
Dr. LoSassoCertainly could be — at least it's an indicator that something hurts. Not necessarily an emergency visit, but usually that develops over a period of time, and you'll typically notice what sets them off. Especially in an old dog that suddenly gets cranky when a younger dog tries to play — that's probably an arthritic issue. It's hard to say definitively, but pain anywhere can throw off their attitude. We also see behavioral changes tied to brain changes, especially in older dogs.

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