Clinical Management of Chronic Pain

Epidemiology

Pain is an extremely common symptom. In the United States, acute pain motivates more people to seek medical care than any other single complaint.² Roughly 1 in 4 people in this country lives with “serious pain,” and 1 in 6 is disabled to some extent by pain.² Fortunately, healthcare professionals have a wide range of options at their disposal for managing both acute and chronic pain.

Treatment Options

Pharmacologic treatments fall into 3 main categories¹

• Nonopioids (nonsteroidal anti-inflammatory drugs and acetaminophen)
• Adjuvant analgesics (such as antiepileptic drugs and tricyclic antidepressants)
• Opioids

Nonopioids and Adjuvant Analgesics

Nonopioid pain medications include nonsteroidal anti-inflammatory drugs (NSAIDs) and analgesics such as acetaminophen.

Nonsteroidal anti-inflammatory drugs work to reduce inflammation,¹ as a result of COX-2 inhibition. They inhibit cyclooxygenase (COX-1 and COX-2) and therefore decrease prostaglandin synthesis.⁵ NSAIDs are also analgesic and sufficient to manage many forms of pain.¹ They can also be combined with opioids.¹

These drugs, however, have a dose ceiling and may cause gastric bleeding or renal toxicity.¹

Some commonly prescribed NSAIDs include ibuprofen, naproxen, indomethacin, diclofenac, piroxicam, and celecoxib.¹

Analgesics include acetaminophen, which may work by inhibiting COX-3 receptors.⁵ Analgesics relieve pain and generally do not cause renal toxicity or gastric bleeding.⁵

Risks associated with acetaminophen include possible hepatotoxicity and, at high doses, interference with anticoagulants.⁵

Opiate Therapy

“Opioid” refers to all medications related to opium. Morphine and codeine are obtained from the opium poppy, while hydromorphone and oxymorphone are synthetically derived from natural opiates.⁶ Opioids work by mimicking the effects of natural neurotransmitters at opioid receptors throughout the nervous system.⁶

Healthcare professionals have relied on opioids to relieve pain for thousands of years. Today many healthcare professionals agree that opioids can be a safe and effective component of pain management.^7,8

Short-acting opioids are indicated for acute, mild to moderate pain, while long-acting opioids are indicated for round-the-clock management of moderate to severe pain.⁹ Opioid medications are valuable analgesics because of their effectiveness in alleviating moderate to severe pain that is inadequately responsive to nonopioid therapy.¹ Opioids have other attractive treatment properties, including

• No dose ceiling
• No risk for end-organ damage

However, activation of opioid receptors within the limbic system can cause mood elevation—an effect linked to abuse and addiction potential.^1,10 While the risk of addiction exists, it is an infrequent occurrence among those with chronic pain.^11,12

For healthcare professionals who prescribe opioids, there is also concern about increased regulatory scrutiny and risk of addiction among patients.^7,13

Nonpharmacologic Treatments

Nonpharmacologic interventions can supplement drug therapy for those in chronic pain.¹ Nonpharmacologic treatments can be tailored to each patient’s needs and address situational factors that exacerbate the experience of pain, such as mood, state of relaxation, coping skills, and quality of sleep.¹ Cognitive and behavioral interventions include hypnosis, biofeedback, and instruction in relaxation techniques.¹ Other modalities are physical in nature, such as application of heat or cold, massage, immobilization, and electroanalgesia. Many of these techniques are employed as components of a rehabilitation program.¹ While noninvasive treatments plus pharmacotherapy are generally adequate, some patients require surgical interventions to manage intractable pain.¹

NEXT Challenges of Responsible Pain Management