Complex regional pain syndrome (CRPS) is a chronic health problem that causes long-lasting pain. Normally, pain is short-term and goes away as the body heals. But with this condition, pain doesn't fade with time. Instead, ongoing pain might get worse instead of better as days and weeks pass.

There are two types of CRPS:

• Type-I CRPS is not tied to a direct nerve injury.
• Type-II CRPS occurs after a nerve injury.

Experts aren't sure what causes this syndrome. But they believe that nerve damage is involved. In most cases, the condition occurs after some type of injury to the affected area. But this is not always the case.

Doctors view this disease as an abnormal response by the body. The nerve endings that control pain in an injured part of the body may become too sensitive to the chemical messengers carried by the sympathetic nervous system. These chemical messengers are called catecholamines. They may stimulate the pain and be linked to other symptoms. The roles of inflammation and the immune system are also being studied.

If you have this syndrome, you may have these symptoms:

• Persistent, burning pain in an arm, leg, hand, foot, or other part of your body
• Mild or severe pain
• Swelling
• Sweating
• Dramatic changes in skin color and skin temperature
• Muscle strength and movement that are less than normal
• Stiffness in affected joints

There is no specific test to diagnose this syndrome. Your doctor can diagnose it based on your health history, such as having an injury, and based on the symptoms you have. Other conditions can cause similar symptoms. So a careful physical exam is important. Sometimes tests are done to rule out some of these other health problems. Certain tests can help determine if autonomic nerves are injured and linked to the pain.

Autonomic nerve tests can be done to confirm a problem with these nerves. This testing can measure blood flow and sweating, among other things. Changes in bone that are seen on X-rays can support the diagnosis.

Your doctor may suggest a sympathetic nerve block. This can help you and your doctor find out if your sympathetic nervous system is causing your pain. It involves injecting an anesthetic into the nerves near the spine. If the nerve block helps your pain, your doctor may give you a series of nerve blocks for ongoing relief.

This syndrome has no cure. But sometimes the symptoms get better or stop on their own. Some evidence suggests that early treatment, particularly with physical therapy, can help limit the disease. But this has not yet been proven in studies.

Treatment focuses on easing the pain. It may include:

• Pain medicines.
• Antidepressants.
• Antiseizure medicines.
• Oral steroid medicines.
• Sympathetic nerve blocks.
• Physical therapy.
• Electrical stimulation of the spinal cord or certain nerves.
• Behavioral therapy and psychotherapy.
• Acupuncture and other alternative therapy.

In severe cases, your doctor may inject medicines directly into the fluid around the spinal cord. But it is not clear how well these treatments work.

The outcome in CRPS can vary a lot. So it's important that CRPS is diagnosed and treated as soon as possible. You will then have the best chance for a full recovery. Follow your doctor's instructions for taking pain medicines and for doing physical therapy or for exercising, if it is part of your treatment plan.

Physical therapy and exercise that keeps the painful limb or body part moving can often improve blood flow and ease symptoms. It can also help improve the affected limb's flexibility, strength, and function. If needed, occupational therapy can help you learn new ways to work and do daily tasks.

CRPS can cause emotional or psychological issues for those affected and for their families. People with this condition might have depression, anxiety, or posttraumatic stress disorder. All of these can make the pain seem worse and make rehabilitation efforts harder. Let your doctor know how you are feeling. There often are ways to help.

Some other types of therapies have been used to treat other painful conditions. These include behavior changes; acupuncture; chiropractic treatment; relaxation methods, such as biofeedback and progressive muscle relaxation; and guided motion therapy. It's not clear if they are helpful for CRPS. Talk with your doctor before starting any new type of treatment.

If you have this syndrome and are being treated, talk with your doctor about when you should contact them.

Your doctor will likely advise you to contact them if any of your symptoms get worse or if you develop any new symptoms.

Some people with this condition might need strong pain medicines. These can have their own side effects, such as drowsiness, confusion, or changes in consciousness. Let your doctor know if you have these or any other symptoms while taking pain medicines. Your doses might need to be adjusted.

• CRPS is a chronic health condition that causes long-lasting pain. It is often caused by an overreaction in the body to a physical injury.
• Symptoms include constant pain ranging from mild to severe. You may also sometimes have swelling, sweating, and changes in skin color and temperature in the affected area.
• CRPS might go away on its own over time. But in some people, the symptoms can last or even get worse. Common treatments are pain medicines, physical therapy, electrical nerve stimulation, and injections of an anesthetic into the nerves.

Tips to help you get the most from a visit to your doctor:

• Know the reason for your visit and what you want to happen.
• Before your visit, write down questions you want answered.
• Bring someone with you to help you ask questions and remember what your doctor tells you.
• At the visit, write down the name of a new diagnosis and any new medicines, treatments, or tests. Also write down any new instructions your doctor gives you.
• Know why a new medicine or treatment is prescribed and how it will help you. Also know what the side effects are.
• Ask if your condition can be treated in other ways.
• Know why a test or procedure is recommended and what the results could mean.
• Know what to expect if you do not take the medicine or have the test or procedure.
• If you have a follow-up appointment, write down the date, time, and purpose for that visit.
• Know how you can contact your doctor if you have questions, especially after office hours or on weekends.