Pain Recognition in Cats: Assessment Tools and Welfare
Cats are notoriously stoic, making pain recognition challenging. This page reviews validated pain assessment tools, common painful conditions in cats, and welfare-positive management approaches.
The Challenge of Feline Pain Recognition
Cats have evolved as both predators and prey, making stoic behaviour during pain adaptive—showing weakness invites predation. In domestic settings, this evolutionary heritage means cats frequently mask pain signs, leading to underrecognition and undertreatment. Pain in cats may manifest as: subtle behaviour changes (reduced activity, withdrawal, altered grooming, changed posture); elimination outside the litter tray; reduced interaction with owners; altered facial expression; or aggression when painful areas are touched. Active pain assessment is essential rather than assuming pain is absent because overt signs are lacking.
Feline Grimace Scale
The Feline Grimace Scale (FGS) is a validated, photo-anchored assessment tool measuring five action units: orbital tightening (squinting); muzzle tension; whisker position and shape; ear position; and head position. Each unit is scored 0 (absent), 1 (moderate), or 2 (obvious), for a maximum score of 10. FGS can be used in clinical settings and by trained owners at home. It detects acute pain and is sensitive to analgesic treatment effects. FGS is now taught in veterinary curricula and is the recommended acute pain assessment tool for hospitalised cats in WSAVA guidelines.
Chronic Pain Recognition
Chronic pain (arthritis, dental disease, otitis, internal organ pain) is even harder to recognise than acute pain. Indicators include: reduced jumping height and frequency; difficulty accessing elevated resting sites; reluctance to groom hindquarters; reduced play frequency; social withdrawal; altered sleep patterns; and personality changes (irritability or increased clinginess). Owner-completed questionnaires (Feline Musculoskeletal Pain Index, FMPI; Montreal Instrument for Cat Arthritis Testing for owners and veterinarians, MI-CAT) provide structured chronic pain assessment tools.
Arthritis: The Most Common Chronic Pain Source
Feline osteoarthritis is present radiographically in approximately 90% of cats over 10 years of age, with approximately 45% showing clinical signs. Despite extraordinary prevalence, it remains massively underdiagnosed—owners attribute mobility changes to 'normal aging' rather than treatable pain. Welfare is compromised over years of unrecognised and untreated chronic pain. Effective management includes: NSAIDs (meloxicam at appropriate feline-specific doses), gabapentin for neuropathic components, environmental modification, and weight management.
Dental Pain
Dental disease is extremely prevalent in cats: periodontal disease affects approximately 80% of cats over 3 years; tooth resorption (a painful condition unique to cats) affects 30-70% of adult cats. Cats rarely stop eating from dental pain—they adapt their chewing technique—leading owners to conclude dental health is adequate. Active dental assessment under anaesthesia, probing and radiographing all teeth, reveals painful disease invisible to visual examination alone. Post-dental treatment behaviour change (increased activity, improved appetite, greater social engagement) in many cats retrospectively confirms the extent of pre-treatment welfare compromise.
Perioperative Pain Management
Cats require proactive perioperative pain management—pain prevention is more effective than treating established pain. Multimodal analgesia (combining NSAIDs, opioids, local anaesthesia, and alpha-2 agonists) provides superior pain control compared to single-agent approaches. Feline-specific drug doses, pharmacokinetics, and metabolism (notably limited glucuronidation) require species-specific protocol design rather than scaling from canine protocols. Post-operative pain assessment using FGS or Glasgow CMPS-Feline guides analgesic continuation and rescue analgesia decisions.
Owner Education in Pain Recognition
Owner education about feline pain recognition is a welfare multiplier: owners who recognise pain signs seek veterinary attention earlier, improving outcomes. Educational resources should include: demonstration of normal versus pain-affected behaviour; explanation of the Feline Grimace Scale for home use; specific guidance on arthritis, dental disease, and other common pain sources in cats; and normalisation of analgesic treatment ('cats shouldn't have to live with pain'). Veterinary practice communication consistently underestimates owner capability to monitor and report pain signs with appropriate guidance.
Summary
Pain recognition in cats requires active assessment using validated tools (Feline Grimace Scale, chronic pain questionnaires) rather than passive observation of overt signs. Common chronic pain sources—arthritis and dental disease—are massively underrecognised and undertreated. Welfare-positive feline medicine invests in pain assessment, species-appropriate multimodal analgesia, environmental modification, and owner education to close the substantial gap between actual and ideal pain management for cats.