Rheumatoid Arthritis Health Center
Rheumatoid Arthritis Overview
Arthritis is a general term that means inflammation in a joint. Joint inflammation is characterized by redness, warmth, swelling and pain within the joint.
Rheumatoid arthritis is a type of chronic arthritis that typically occurs in joints on both sides of the body (such as hands, wrists or knees). This symmetry helps distinguish rheumatoid arthritis from other types of arthritis.
In addition to affecting the joints, rheumatoid arthritis may occasionally affect the skin, eyes, lungs, heart, blood, or nerves.
What Are the Symptoms of Rheumatoid Arthritis?
Symptoms of rheumatoid arthritis include:
- Joint pain and swelling
- Stiffness, especially in the morning or after sitting for long periods
- Fatigue
Rheumatoid arthritis affects everyone differently. In most people, joint symptoms develop gradually over several years. But in some, rheumatoid arthritis may progress rapidly and yet other people may have rheumatoid arthritis for a limited period of time and then enter a period of remission.
Who Gets Rheumatoid Arthritis?
Rheumatoid arthritis affects about 1% of the U.S. population. While it is two to three times more common in women than in men, men tend to be more severely affected when they get it. It usually occurs in middle age, however, young children and the elderly also can develop rheumatoid arthritis.
What Causes Rheumatoid Arthritis?
The exact cause of rheumatoid arthritis is unknown, but it is thought to be due to a combination of genetic, environmental and hormonal factors. With rheumatoid arthritis, something seems to trigger the immune system to attack the joints and sometimes other organs. Some theories suggest that a virus or bacteria may alter the immune system, causing it to attack the joints.
Research hasn't been able to determine exactly what role genetics plays in rheumatoid arthritis. However, some people do seem to have a genetic or inherited factor that increases their chance of developing rheumatoid arthritis.
How Does Rheumatoid Arthritis Affect the Body?
Once the immune system is triggered, immune cells migrate from the blood into the joints and joint-lining tissue, called synovium. There the immune cells produce inflammatory substances. The increased number of cells and inflammatory substances within the joint cause irritation, wearing down of cartilage (cushioning material at the end of bones), and swelling and inflammation of the joint lining. Inflammation of the joint lining stimulates it to produce excessive joint fluid within the joint.
As the cartilage wears down, the space between the bones narrows. If the condition worsens, the bones could rub against each other.
As the joint lining expands, it may invade into, or erode, the adjacent bone, resulting in irreversible bone damage. All of these factors cause the joint to become very painful, swollen, and warm to the touch.
How Is Rheumatoid Arthritis Diagnosed?
The diagnosis of rheumatoid arthritis is based on a combination of factors, including:
- The specific location and symmetry of painful joints, especially the hand joints.
- The presence of joint stiffness in the morning.
- Presence of bumps and nodules under the skin (rheumatoid nodules).
- Results of X-ray tests that suggest rheumatoid arthritis.
- Positive results of a blood test called the rheumatoid factor.
WebMD Medical Reference provided in collaboration with the Cleveland Clinic![]()
Important Safety Information
Cymbalta® (duloxetine HCl) is approved for the treatment of depression and generalized anxiety disorder, and for the management of diabetic peripheral neuropathic pain and fibromyalgia.
What should I talk about with my healthcare provider?
Patients on antidepressants and their families or caregivers should watch for new or worsening depression symptoms, unusual changes in behavior, thoughts of suicide, anxiety, agitation, panic attacks, difficulty sleeping, irritability, hostility, aggressiveness, impulsivity, restlessness, or extreme hyperactivity. Call your healthcare provider right away if you have thoughts of suicide or if any of these symptoms are severe or occur suddenly. Be especially observant within the first few months of antidepressant treatment or whenever there is a change in dose.
You should also know that:
- Suicide is a known risk of depression and some other psychiatric disorders.
- Antidepressants may increase suicidal thoughts or behaviors in some children, adolescents, and young adults especially within the first few months of treatment or when changing the dose. No increased risk has been shown for adults over age 24, and risk decreased for those over age 65.
- All patients starting therapy should be monitored appropriately and observed closely for new or worsening depression symptoms, suicidal thoughts or behavior, or unusual changes in behavior.
- Cymbalta® is not approved for use in patients under age 18.
Who should NOT take Cymbalta?
You should not take Cymbalta if:
- You have recently taken a type of antidepressant called a monoamine oxidase inhibitor (MAOI)
- You have uncontrolled narrow-angle glaucoma (an eye disease)
- You are taking Mellaril® (thioridazine)
What other important information should I discuss with my healthcare provider?
Before starting Cymbalta, tell your healthcare provider:
- about all of your medical conditions, including kidney problems, glaucoma, or diabetes
- about your alcohol use
- if you are taking nonprescription or prescription medicines, including those for migraine, to address a possible life threatening condition
- if you are taking NSAID pain relievers, aspirin, or blood thinners. Use with Cymbalta may increase bleeding risk
- if you are pregnant, plan to become pregnant during therapy, or are breastfeeding an infant
While taking Cymbalta, tell your healthcare provider:
- if you have itching, right upper belly pain, dark urine, yellow skin/eyes, or unexplained flu-like symptoms, which may be signs of liver problems. Severe liver problems, sometimes fatal, have been reported
- if you have high fever, confusion, and stiff muscles to address a possible life-threatening condition
- before stopping Cymbalta or changing your dose
- if you experience dizziness or fainting upon standing, especially when first starting Cymbalta or when increasing the dose. Your healthcare provider may periodically check your blood pressure while you are taking Cymbalta
If you have any questions, talk to your healthcare provider before taking Cymbalta.
What are the possible side effects of Cymbalta?
The most common side effect of Cymbalta was nausea. For most people who had it, the nausea was mild to moderate. Other common side effects included dry mouth, sleepiness, constipation, decreased appetite, and, increased sweating. This is not a complete list of side effects.


