Summary

22 items · 20–35 minutes

Why Behavioral Changes Deserve Careful Attention

Animals communicate differently from humans, and distress — whether physical or emotional — frequently surfaces first as a change in behavior. A cat that stops grooming, a dog that refuses food, or a bird that suddenly becomes silent may each be signaling something significant. The challenge for owners is knowing which changes warrant a watch-and-wait approach and which demand prompt veterinary attention.

This checklist is designed to help you systematically observe, document, and respond to behavioral shifts in your pet. It applies broadly to dogs and cats, with notes where other species may differ. For a deeper foundation in reading what your pet is communicating physically, see our practical guide to pet body language.

When to Seek Emergency Care Immediately

Some behavioral changes signal a medical emergency. If your pet collapses, has a seizure, is breathing with visible effort, cannot stand, or shows sudden extreme aggression with no apparent trigger, do not wait — contact a veterinarian or emergency animal hospital right away. This checklist is not a substitute for emergency evaluation.

This checklist is for general educational purposes and does not replace professional veterinary assessment. If your pet is showing signs of acute distress — collapse, seizure, labored breathing, or significant injury — contact a veterinarian or emergency animal clinic immediately.

Tools to Have on Hand

Before working through the checklist, gather a few basic resources that will make your observations more accurate and actionable.

Required

Notebook or pet health app

Log behavioral observations daily with timestamps, enabling you to share a clear timeline with your veterinarian.

Required

Smartphone with video capability

Capture intermittent symptoms — such as limping or tremors — that may not be present during a vet appointment.

Optional

Pet scale (home or at a clinic)

Track weight changes that may accompany behavioral shifts, since unexplained loss or gain is clinically relevant.

Required

Veterinary contact information

Have your regular vet's number and an after-hours emergency clinic number accessible before you need them.

The Behavioral Change Checklist

Work through each group systematically. Mark items you've observed in your pet over the past one to two weeks. For any group where you check multiple items, prioritize sharing those observations with your veterinarian.

Eating and Drinking Habits

Note whether your pet has stopped eating for more than 24 hours (cats) or 48 hours (dogs), as appetite loss beyond these windows typically warrants veterinary contact. Must
Check for a marked increase in water consumption, which can indicate metabolic or kidney concerns — see our guide on increased thirst in pets. Must
Observe whether your pet is eating significantly faster or slower than usual, or dropping food, which may signal dental pain or nausea. Should

Elimination and Litter Box Behavior

Monitor for accidents outside the litter box or usual bathroom area, especially if this is a new behavior in a house-trained animal. Must
Watch for straining, crying during elimination, blood in urine or stool, or significant changes in frequency — these require prompt veterinary evaluation. Must
Note whether stool consistency or color has changed noticeably over more than two days. Should

Social and Interaction Changes

Identify if your pet is withdrawing from family members or hiding in unusual locations more than is typical for their baseline personality. Must
Record any new aggression toward people or other pets, especially if your pet has no history of this behavior — consult a veterinarian to rule out pain before assuming a behavioral cause. Must
Notice whether your pet is seeking more contact and reassurance than normal, which can also indicate stress or discomfort. Should
Check if your pet flinches or avoids being touched in a specific area of their body, which often indicates localized pain. Must

Activity and Mobility

Track any reluctance to jump, climb stairs, or rise from rest, as these can signal musculoskeletal pain especially in older pets. Must
Observe whether your pet is moving more slowly, limping, or favoring a limb, and note when and how often this occurs. Must
Note significant changes in sleep duration or location — pets sleeping far more or far less than usual may be compensating for illness or pain. Should
Watch for restlessness, pacing, or an inability to settle, which are common indicators of anxiety or physical discomfort. Should

Grooming and Coat Condition

Assess whether your pet has stopped self-grooming or shows a visibly deteriorating coat — this is often one of the first signs of systemic illness in cats. Must
Look for new or excessive licking, chewing, or scratching at a specific body area, which can signal skin irritation, pain, or anxiety. Should
Note any new odor from the coat, ears, or mouth, as these can signal infection or dental disease. Should

Vocalization and Sound

Document any new or unusual vocalizations — whining, howling, yowling, or growling — especially at night or when touched. Must
Notice if a typically vocal pet has become unusually quiet or vice versa, as both shifts can indicate distress. Should

Documentation and Escalation

Start a simple daily log using a notebook or phone app: date, observed behavior, duration, and any context (e.g., new food, guests, weather). Must
Take short video clips of any concerning movement or behavior to share with your veterinarian, since many symptoms are intermittent. Should
Schedule a veterinary appointment if you have checked three or more items in this checklist within the past week, or sooner if any single item is acute. Must

Avoid Attributing All Changes to 'Just Getting Older'

It is tempting to assume that slowing down, reduced appetite, or social withdrawal are simply signs of aging. While some changes are age-related, many are treatable conditions — arthritis, dental disease, cognitive dysfunction, or hormonal imbalance — that genuinely reduce quality of life if left unaddressed. Age is never a reason to skip a veterinary evaluation when behavior shifts noticeably.

Do Not Attempt to Self-Diagnose or Self-Treat

Over-the-counter medications intended for humans — including common pain relievers like ibuprofen and acetaminophen — are toxic to many animals. Never administer any medication to your pet without explicit veterinary guidance, even if the symptom seems straightforward.

What to Do After Working Through the Checklist

Once you've identified which behaviors apply to your pet, your next step depends on the pattern you've found.

Multiple items checked in one group — This suggests a concentrated problem worth investigating promptly. Contact your veterinarian and bring your written notes. Changes in eating, elimination, or pain-related behavior especially benefit from early evaluation. Our complementary article on why pets hide pain explains why many animals instinctively mask discomfort.

Single items checked across several groups — This may reflect a broader stress response, often tied to environmental change. Consider recent household shifts: a move, a new family member, schedule disruption, or changes in the home. For pets showing anxiety or fearfulness, evidence-informed strategies for building trust can support gradual recovery.

Senior pets — Age changes the baseline. Older animals develop conditions that mimic behavioral quirks, including cognitive dysfunction, arthritis-related reluctance to move, and metabolic changes. If your pet is in its senior years, our guides on how health needs shift with age and caring for ageing pets provide useful context.

If boredom may be a factor — Not all behavioral changes signal illness. Destructive or repetitive behaviors sometimes reflect understimulation. Our article on how boredom shows up behaviorally can help you distinguish distress from a need for enrichment.

This article is for general informational purposes only and is not a substitute for professional veterinary advice, diagnosis, or treatment. Always consult a licensed veterinarian regarding your pet's specific health needs.

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Pets & Animals Editorial Team · Contributor

Pets & Animals Editorial Team is the collective byline for our editorial team and contributor network. Articles published under this byline or an editorial pen name are researched, written, and reviewed according to our editorial standards for clarity, consistency, and independence before publication.

The content on this site is for informational purposes only and is not a substitute for professional advice. Always consult a qualified professional for guidance specific to your situation.