Synopsis
Recognise pain as a multidimensional clinical presentation, identify emergencies and reversible causes, formulate nociceptive, neuropathic and contextual mechanisms, and measure treatment against function and goals rather than intensity alone.
- Pain is whatever the patient reports, but assessment must also identify mechanism, cause, emergency features, functional effect and safe treatment options.
- First-line history uses site, onset, quality, radiation, severity, timing, triggers, associated features, previous response and impact on sleep, movement and roles.
- Classify each pain as somatic, visceral, neuropathic or mixed; one person may need a separate formulation for several concurrent pains.
- Ask about continuous background pain, spontaneous breakthrough, incident pain and end-of-dose failure because each pattern changes the plan.
- Use a patient-selected numeric, verbal or visual scale consistently, but anchor improvement to an activity or goal the person values.
- First-line examination is directed by location and red flags and includes neurological, musculoskeletal, vascular, abdominal and skin assessment where relevant.
- The gold standard is repeated patient-centred formulation with examination and response review; no scan, biomarker or pain score independently proves the experience or mechanism.
- Review prescription and non-prescription analgesics, total opioid exposure, rescue use, adherence, alcohol or sedatives, organ function and who administers medicines.
- Cancer pain and pain in advanced illness can coexist with chronic primary pain; opioid escalation is not automatically appropriate for every mechanism.
Key red flags
Back pain with new weakness, sensory change, gait deterioration or bladder or bowel dysfunction requires emergency metastatic spinal cord compression assessment.
Sudden focal bone pain, deformity, inability to weight bear or pain on minimal movement suggests pathological fracture or impending structural failure.
Severe escalating pain with fever, haemodynamic change, peritonism, a hot joint or immunosuppression needs urgent infection or surgical evaluation.
New headache with vomiting, focal neurology, seizure or altered consciousness may indicate raised intracranial pressure or intracranial bleeding.
Pain out of proportion, a cold limb, absent pulses, new swelling or chest symptoms requires immediate vascular or thromboembolic assessment.
Marked drowsiness, hallucinations, myoclonus, pinpoint pupils or respiratory slowing during opioid therapy suggests toxicity rather than uncontrolled pain.
A patient expressing suicidal intent, unsafe opioid use or coercive medicine control requires direct risk, safeguarding and access assessment.
Myoclonus, hallucinations, allodynia, diffuse pain and sedation during escalating opioid exposure should prompt toxicity review.
Investigation priorities
Define each pain's site, time course, quality, severity, triggers, associated features, response, meaning and functional impact.
Management branches
A patient reports new, changed or inadequately controlled pain.
- Identify immediate red flags, give proportionate relief and describe each pain's timing, quality, triggers, functional effect and associated features.
- Examine the relevant systems, reconcile all medicines and organ function and use targeted tests only where results could change management.
- Agree a mechanism-based plan, one measurable goal, rescue and safety advice and a review interval matched to severity and titration risk.