Drugs Used to Control Chronic Pain
A wide variety of over-the-counter and prescription medicines have been shown to help ease chronic pain, including:
• Pain relievers. Many pain patients get some relief from common pain medicines such as acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs), and analgesics like aspirin, ibuprofen, ketoprofen, and naproxen. These drugs are considered safe, but they are not risk-free. For example, taking too much acetaminophen can cause liver damage or even death, especially in people with liver disease. NSAIDs can cause ulcers and raise the risk for heart attack and kidney trouble.
• Antidepressants. Several drugs approved by the FDA to treat depression are also prescribed by doctors to help relieve chronic pain. These include tricyclic antidepressants such as amitriptyline (Elavil), imipramine (Tofranil), clomipramine (Anafranil), desipramine (Norpramin), doxepin (Sinequan), and nortriptyline (Pamelor). The pain-relieving effect of tricyclics appears to be distinct from the mood-boosting effect, so these drugs can be helpful even in chronic pain patients who are not depressed.
Other antidepressants used to treat pain include venlafaxine (Effexor) and duloxetine (Cymbalta), which the FDA has approved to treat fibromyalgia and diabetic nerve pain. These drugs are members of a class of medications known as serotonin and norepinephrine reuptake inhibitors (SNRIs). They seem to be about as effective at treating chronic pain as tricyclics, but are less likely to cause dry mouth, sedation, urinary retention, and other side effects.
When used at appropriate doses with careful monitoring, these drugs can be safe and effective treatment for chronic pain. But be sure to discuss the risks, benefits, and research behind any drug with your doctor.
• Anticonvulsants. Several drugs originally developed to treat epilepsy are also prescribed for chronic pain. These include first-generation drugs like carbamazepine (Tegretol) and phenytoin (Dilantin), as well as second-generation drugs like gabapentin (Neurontin), pregabalin (Lyrica), and lamotrigine (Lamictal). Gabapentin and Lyrica are FDA-approved to treat pain.
The first-generation drugs can cause an unstable gait (ataxia), sedation, liver trouble, and other side effects. Side effects are less of a problem with second-generation drugs.
• Opioids. Codeine, morphine, oxycodone, and other opioid medications can be very effective against chronic pain, and they can be administered in many different ways, including pills, skin patches, injections, and via implantable pumps.
Many pain patients and even some doctors are wary of opioids (also known as narcotics) because they have the potential to be addictive. Except for patients with a history of addictive behavior, pain experts say the potential benefit of narcotic therapy for chronic pain often outweighs the risk.
"It’s a matter of balance," says Chou. "People do need to be concerned about the risk posed by opioids. But as a physician, I think it is inappropriate not to use medications that can help people, if the risks can be managed."
Generally, doctors who prescribe opiod treatment monitor patients with chronic pain carefully.