AN ONGOING CE PROGRAM OF THE UNIVERSITY OF FLORIDA COLLEGE OF PHARMACY AND DRUG TOPICS
Pain is a common clinical condition in the United States and the most common reason patients seek healthcare. It is described by the International Association for the Study of Pain as an unpleas- ant sensory and emotional experience as- sociated with actual or potential tissue damage, or an experience described in terms of such damage.
Types of acute or chronic pain causing patients to seek treatment . include back, neck, abdominal, chest, or headache pain, sprains, broken bones, and cuts or puncture wounds. This article will discuss the pathophysiology of various types of pain and available therapies.
Each year, an estimated 25 million Americans experience acute pain due to injury. Another 50 million suffer from chronic pain. Many patients with chronic pain have lived with their pain for more than 5 years, and they experience pain almost every day of the week. Long-term disability is caused by chronic pain more frequently than by any other diagnosis. At some point, one-third of all Americans will experience severe chronic pain.
Pain is often undertreated, even though we possess sufficient knowledge and resources to manage pain in an estimated 90 percent of individuals. A considerable body of literature supports the assertion that many patient populations suffering from many types of pain are undertreated.
Barriers to treatment
There are several barriers to adequate pain treatment. Changes in the healthcare system that have been made during the past 20 years, such as shifts from inpatient to outpatient treatment and changing reimbursement policies, have introduced new barriers to care. Patient care has become more fragmented, leading to a lack of coordination of care across the system. And managed-care organizations may impede patient access to pain specialists, facilities specializing in pain management, and some drug therapies.
Healthcare professionals contribute greatly to the undertreatment of pain through attitudes, beliefs, and behaviors contrary to best pain-management practices. Often, healthcare professionals refuse to accept the patient's self report as the most reliable indicator of pain. In documented studies, many healthcare professionals have shown themselves to be poor at assessing pain or they have failed to accept the patient's assessment of his/her pain. Healthcare providers are often overly concerned about the regulatory aspeas associated with narcotic use, iatrogenic addiction, or analgesic side effects of drugs used to treat pain.
For their part, patients and family members introduce barriers derived from low expectations of obtaining relief, fear of addiction, fear of being perceived as addicted, or discomfort with analgesic side effects. Other patient-connected factors contributing to undertreatment of pain include financial constraints and poor adherence to treatment regimes.
There are many different ways to classify pain. Acute vs. chronic, malignant vs. nonmalignant, and somatic vs. visceral vs. neuropathic are all common classifications.
Acute vs. chronic is one common classification that helps us guide drug therapy. Acute pain serves a physiologic purpose and it resolves with healing. Chronic pain has no physiologic value and it may persist despite healing of injured tissue. Chronic pain can lead to permanent negative changes ("neural plasticity'') in the nervous system.
Malignant pain is associated with progressive disease that may be life-threatening. Most people think of cancer when they hear the term malignant, but malignant pain can be caused by a number of other disease states, such as neurological diseases or AIDS.
Neuropathic pain results from damage to nerves or pathologic changes in the peripheral or central nervous system. Common examples of neuropathic pain are post-herpetic neuralgia and the peripheral neuropathies associated with alcoholism or diabetes. …