Chronic pain is pain that lasts or recurs for months or years.
Usually, pain is considered chronic if it does one of the following:
Lasts for more than 3 months
Lasts for more than 1 month after the injury or problem that originally caused pain has resolved
Recurs off and on for months or years
Is associated with a chronic disorder (such as cancer, arthritis, diabetes, or fibromyalgia) or an injury that does not heal
(See also Overview of Pain.)
Chronic pain sometimes occurs when nerves become more sensitive to pain. For example, the original cause of the pain may repeatedly stimulates the nerve fibers and cells that detect, send, and receive pain signals. Repeated stimulation can change the structure of nerve fibers and cells (called remodeling) or make them more active. As a result, pain may result from stimulation that might not ordinarily be painful, or painful stimuli may seem more severe. This effect is called sensitization.
Also, areas of muscle or connective tissue may become very sensitive and tender to the touch. These areas are called trigger points because touching these areas frequently triggers unexplained pain that radiates to other areas of the body.
Did You Know...
|
Chronic disorders (such as cancer, arthritis, diabetes, or fibromyalgia) can cause chronic pain. Chronic pain can also result from an injury, even a mild injury if nerve fibers and cells have become sensitized.
Anxiety, depression, and other psychologic factors may help explain why some people experience pain as more unpleasant than others do and why pain limits their activities more. For example, people with chronic pain know it will recur and may become fearful and anxious as they anticipate the pain. Fear and anxiety can reduce the production of substances that reduce the sensitivity of nerve cells to pain. These changes in sensitivity to pain partly account for pain that persists after its cause resolves and for pain that feels more severe than expected.
Sometimes what originally caused the pain is obvious—for example, when people have had an injury that resulted in chronic back pain. Or the cause may be unknown—for example, when people have a chronic headache.
Symptoms of Chronic Pain
Chronic pain may occur in different parts of the body in different people (for example, it may occur in the back in one person and in the fingertips in another). Also, the sensation of pain may be different. For example, the pain may feel like throbbing, stabbing, burning, or stinging. It may be constant or may come and go, and the intensity of the pain may vary.
People with chronic pain often also feel tired, have problems sleeping, lose their appetite and/or taste for food, and lose weight. Their sex drive may decrease. These problems develop gradually. Constant pain can prevent people from doing what they usually enjoy. They may become depressed and anxious. They may stop their activities, withdraw socially, and become preoccupied with physical health.
Diagnosis of Chronic Pain
A doctor's evaluation
Sometimes a mental health evaluation
Doctors thoroughly evaluate the person to identify the cause of pain and its effect on daily life. If no cause is identified, doctors then focus on relieving pain and helping the person function better.
Doctors ask the person whether the person feels depressed, has anxiety and is sleeping well. Identifying these symptoms is critical because they can make the pain worse and, if present, must be treated if the pain is to be effectively treated. A formal mental health evaluation may be necessary.
Treatment of Chronic Pain
Drugs to relieve pain
Physical methods (such as physical therapy)
Psychologic and behavioral therapy
If a cause of chronic pain is identified, it is treated.
Treatment of chronic pain may include the following:
Drugs to relieve pain (analgesics)
Physical methods, such as physical therapy or occupational therapy
Complementary and integrative pain-relieving techniques, such as acupuncture, massage, and transcutaneous electrical nerve stimulation (TENS)
Psychologic and behavioral therapy
If treatments are ineffective, doctors may refer people to a pain clinic.
Drugs
In most people taking pain relievers (analgesics) for chronic pain, the pain's intensity varies throughout the day. Intensity varies based on several factors, such as the following:
Characteristics of the affected nerves (for example, how quickly they send signals and where the nerves are located)
Activities that can cause pain (such as moving or touching the affected area)
Stress
Dose or schedule of pain relievers
Depending on the severity of the pain, the following types of drugs may be used to treat chronic pain:
Nonsteroidal anti-inflammatory drugs (NSAIDs)
Drugs called adjuvant analgesics (such as antidepressants or antiseizure drugs)
Sometimes a combination of drugs may relieve pain more effectively than a single drug.
nonsteroidal anti-inflammatory drugs (NSAIDs)
Adjuvant analgesics are commonly used to treat chronic pain. These drugs are thought to work by changing the way nerves process pain (rather than directly stopping the sensation of pain).
The adjuvant analgesics most commonly used for pain are
Oral and topical local anesthetics
Opioids are used only if other drugs and treatments (such as physical therapy) have not been effective. Use of opioids is limited because they may have side effects, such as an opioid use disorder (addiction), slowing of breathing (respiratory depression), and death due to overdose. Opioids are most often used to treat moderate to severe pain due to cancer or to other disorders that shorten lifespan (terminal disorders). Opioids are also used as part of hospice care for people at the end of life.
Before prescribing opioids for any type of chronic pain, doctors consider the following:
What the usual treatment approach is
Whether there are other treatments that could be used
Whether the person has a high risk of side effects from an opioid
Whether the person is at risk of misuse or abuse of an opioid drug or is likely to use the drugs for other purposes (for example, to sell them)
Doctors may refer people to a pain specialist or a mental health care practitioner who has expertise in substance misuse if the risk of having a problem is high. For example, people who have had an addiction usually need a referral.
When opioids are prescribed for chronic pain, doctors explain the nature of the person's disorder (if known) and the risks and benefits of other possible treatments, including nonopioid drugs and no treatment. Doctors ask the person about their goals and expectations. They usually give the person written information that describes the risks of taking opioids. After the person discusses this information with the doctor and understand it, the person is asked to sign an informed consent document.
When doctors prescribe an opioid for chronic pain, they explain the risks and side effects of opioids. People are advised
Not to drink alcohol or take antianxiety drugs or sleep aids when taking the opioid
To take the recommended dose at the recommended times and not to change the dose
To store the opioid in a safe, secure place
Not to share the opioid with anyone
To contact their doctor if the drug makes them drowsy or they have any other side effects (such as confusion, constipation, or nausea)
To dispose of unused pills as directed
If an opioid is prescribed, doctors have usual practices to ensure the person's safety. Doctors typically ask the persons to get opioid prescriptions only from one doctor and fill prescriptions at the same pharmacy every time. They see the person for follow-up visits frequently and monitor the use of the drug to make sure it is safe and effective. For example, doctors may periodically test the person's urine to determine whether the drug is being taken correctly. They also ask the person to sign an agreement that specifies conditions required for opioid use, including any monitoring that may be needed.
For people with pain due to cancer or another terminal disorder, concerns about side effects should not limit the use of opioids because side effects can usually be prevented or managed, and addiction is less of a concern.
Physical or occupational therapy
Physical or occupational therapists use various techniques to try to relieve chronic pain and help people function better. If trigger points are present, practitioners may use a spray to cool the area, then stretch the muscle. This method (called stretch and spray) can help lessen pain. Wearing an orthosis (a device that supports damaged joints, ligaments, tendons, muscles, and bones) helps some people.
Sometimes doing exercises or increasing activity level helps. For example, walking regularly can help relieve lower back pain more effectively than resting in bed.
Physical therapists and occupational therapists can help people with chronic pain find ways to do their daily activities with less pain.
Complementary and integrative medicine
Complementary and integrative medicine may be used to treat chronic pain. For example, doctors may suggest one or more of the following:
Mind-body techniques (such as meditation, yoga, and tai chi)
Manipulation and body-based therapies (such as chiropractic or osteopathic manipulation and massage therapy)
Energy-based therapies (such as therapeutic touch and Reiki)
Counseling and behavioral techniques
Various techniques (such as relaxation training, distraction techniques, hypnosis, and biofeedback) can sometimes help control pain. Distraction techniques may involve guided imagery. For example, people may be instructed to imagine a scene that is calming and comforting, such as resting on a beach or lying in a hammock.
Counseling or psychotherapy can help people function better, even if it does not reduce pain. Doctors may recommend specific ways to gradually increase physical and social activities. People are advised not to let pain derail their commitment to better functioning. When this approach is used, many people report a decrease in pain. Doctors applaud progress, encourage people to continue improving, and continue to treat the pain as needed.
Doctors may also talk with family members or fellow workers to discourage them from doing anything that keeps the person focused on the pain. For example, they should not constantly ask about the person's health or insist that the person do no chores.
Nerve block
A nerve block is frequently used to treat pain caused by damage to a specific large nerve. For this procedure, a nerve pathway that transmits pain signals is disrupted by one of the following:
Injecting the area around the nerves with a local anesthetic to prevent the nerves from sending pain signals (doctors commonly use ultrasonography to help them locate the nerves to be treated)
Injecting the area around nearby collections of nerve cells called ganglia to help regulate the transmission of pain signals
Freezing the nerve (cryotherapy)
Burning the nerve with a radiofrequency probe
Nerve blocks are often used to treat low back pain caused by pressure on (compression of) spinal nerves (which connect the spinal cord with other parts of the body). Nerve blocks may also be used to treat severe cancer pain near the end of life and severe, persistent neuropathic pain when drugs cannot relieve the pain.
Pain rehabilitation programs
Doctors may recommend a pain rehabilitation program for people with chronic pain. These programs are managed by an interdisciplinary team that includes psychologists, physical therapists, doctors, nurses, and sometimes occupational therapists and integrative medicine practitioners. The programs include education. cognitive behavioral therapy, physical therapy, simplification of the drug regimen, and sometimes gradually decreased use of a pain reliever. They focus on the following:
Restoring function
Improving quality of life
Helping people control their own life, despite their chronic pain
