Understanding Centralized Pain
For some people, chronic pain is its own disease.
First used to describe pain that occurs after a brain, brainstem or spinal cord injury, centralized pain now describes any pain that happens when the central nervous system doesn’t process pain signals properly. The condition can also be called “central sensitization” “central amplification” and “central pain syndrome.” Several conditions, such as complex regional pain syndrome, fibromyalgia, irritable bowel syndrome and temporomandibular joint disorder are examples. In some people, chronic arthritis pain can also become centralized; the pain essentially becoming its own disease.
Most people view pain as having an underlying cause; once you treat the cause, the pain should disappear. Accordingly, getting rheumatoid arthritis (RA) under control by taking disease-modifying drugs (DMARDs) or biologics should eliminate the joint pain. And replacing a joint damaged by osteoarthritis (OA) should eliminate pain in that joint.
Often, these measures work and eliminate or significantly reduce the pain. But as many people with well-controlled RA or artificial joints know, pain often lingers. Why that happens is not well understood, and effective treatment can be hard to find.
Chronic Pain and Brain
Research shows that chronic pain changes the brain itself. Doctors now believe that chronic pain turns independent, essentially becoming its own disease. Its home isn’t in the joint that may have been its initial starting point. If you have inflammation that hurts over long periods of time, that pain message is being sent to the brain continuously. The neurons that carry the message begin to change and may become more efficient messengers. The result? Your brain may begin to misread a small message of pain as a big one. Doctors call this “centralized pain.”
About 20 percent of patients with OA who have had their knee or hip replaced continue to have chronic pain. The pain has likely become centralized—it is no longer caused by the inflammation or injury. Now the pain is driven by dysfunction in the central nervous system (CNS).
How to Get Help With Chronic Pain
More doctors now understand the importance of treating chronic pain and centralized pain as its own disease. Your doctor can help you find treatments that address the changes in the brain in addition to treating the condition that jump-started your pain. Here is how you can help your doctor find the right treatment for you.
Don’t Tough It Out
Chronic pain is pain that has lasted three months or longer, or pain that persists beyond the expected healing time of an injury. Take steps to stop pain before it becomes chronic or centralized. You may be worried about medication side effects or you feel like you can handle the pain. But knowing how pain affects the brain, it may be wiser to take pain relievers just enough to prevent the brain changes that can come with untreated pain.
Give Your Doctor Details
Make your pain a priority. If you don’t say it bothers you, your doctor may not focus on it. Tell him where the pain is, how it feels, and how long it’s been there. Also mention what you cannot do with your pain. For example, “I can’t brush my hair or shower.” Consider keeping a pain diary where you can write down how you feel each day and discuss it with your doctor during your appointment.
Ask About CNS Meds
Some antidepressant medications such as duloxetine (Cymbalta) and certain epilepsy drugs such as pregabalin (Lyrica) are being successfully used to treat centralized pain conditions. Chemicals called norepinephrine and serotonin play a role in the body’s pain-inhibition system. Some antidepressants increase those chemicals, so you have less pain. Pregabalin was the first FDA-approved drug for treating fibromyalgia. In people with fibromyalgia, it changes the way pain signals are processed in the brain, leading to less pain.
Consider a Pain Center
If you’re not getting pain relief, ask your doctor to refer you to a pain center. Look for a one that has a mix of physicians, physiatrists, psychiatrists, physical therapists and psychologists.
Learn more about pain and ways to control it in our Pain Toolkit.