(pān) [Fr. peine, fr L. poena, a fine, a penalty, punishment] As defined by the International Association for the Study of Pain, an unpleasant sensory and emotional experience arising from actual or potential tissue damage or described in terms of such damage. Pain includes the perception of an uncomfortable stimulus and the response to that perception. About half of those who seek medical help do so because their primary complaint is pain. Pain may arise in nearly any organ system and may have different characteristics in each system. Musculoskeletal pain, for example, is often exacerbated by movement and may be accompanied by swollen joints or muscle spasm. Myofascial pain is marked by trigger-point tenderness. Visceral pain is often diffuse or vaguely localized, but pain from the lining of body cavities is often localized precisely, very intense, and sensitive to palpation or movement. Nerve pain usually stings or burns; it may be described as numbness, tingling, or shooting sensations. Colicky pain fluctuates in intensity from severe to mild and usually occurs in waves.
Several factors influence the experience of pain, such as the nature of the injury or illness causing the symptom, the physical and emotional health of the patient, the acuity or chronicity of the symptom, the social milieu and/or cultural upbringing of the patient, neurochemistry, memory, and personality. SEE: table.
SYMPTOMS: Many clinicians use the mnemonic COLDER to aid the diagnosis of painful diseases. They will ask the patient to describe the Character, Onset, Location, and Duration of their painful symptoms, the features that Exacerbate or Relieve it. For example, the pain of pleurisy is typically sharp in character, acute in onset, located along the chest wall, and long-lasting; it is exacerbated by deep breathing or coughing and is relieved by analgesics or by holding still. By contrast, the pain of myocardial ischemia is usually dull or heavy, gradual in onset, located substernally, may be exacerbated by activity (but not by taking a breath or coughing), and relieved by nitroglycerin.
Usual Adult Doses and Intervals of Drugs for Relief of Pain
|Nonopioid Analgesics || |
|Generic Name ||Dose, mg* ||Interval ||Comments |
|Acetylsalicylic acid ||325–650 ||4–24 hr ||Enteric-coated preparations available |
|Acetaminophen ||650 ||4 hr ||Avoid in liver failure |
|Ibuprofen ||400–800 ||4–8 hr ||Available without prescription |
|Indomethacin ||25–75 ||8 hr ||Gastrointestinal and kidney side effects common |
|Naproxen ||250–500 ||12 hr ||Delayed effects may be due to long half-life |
|Ketorolac ||15–60 IM ||4–6 hr ||Similar to ibuprofen but more potent |
|Opioid Analgesics || |
|Generic Name ||Parenteral Dose (mg) ||PO Dose (mg) ||Comments |
|Codeine ||30–60 every 4 hr ||30–60 every 4 hr ||Nausea common |
|Hydromorphone ||1–2 every 4 hr ||2–4 every 4 hr ||Shorter acting than morphine sulfate |
|Levorphanol ||2 every 6–8 hr ||4 every ...|