About Ankylosing Spondylitis (AS)

Ankylosing spondylitis (AS) is a disease that can cause pain and inflammation of the joints of the spine. AS usually affects the joints between the vertebrae and almost always the sacroiliac joints (the area where your spine meets your pelvis). It also causes inflammation at the spot where the tendons and ligaments join the bone. In many people, joints of the arms and legs can also be affected. If left untreated, it eventually can cause the affected spinal bones to fuse together. Early diagnosis and treatment helps manage symptoms and may help to limit damage to the spine and damage to other joints.

A few of the joints typically affected by AS

Ankylosing Spondylitis (AS) can affect the joints between the vertebrae, the sacroiliac joints (the area where your spine meets your pelvis), knees, hips, ankles, and joints of the hands and feet.
Ankylosing spondylitis can affect the joints between the vertebrae, the sacroiliac joints (the area where your spine meets your pelvis), hips, and shoulders, as well as other joints.

What causes AS?

The cause of ankylosing spondylitis is unknown, but AS is thought to be a disease of the immune system. The immune system protects the body from infections and diseases. It is believed that, among a number of changes in the immune system, there are increased levels of an active form of a protein called tumor necrosis factor (TNF) that plays a role in the inflammation associated with AS.

Genetic factors seem to contribute to the risk of developing ankylosing spondylitis. People who have a gene called HLA-B27 are at an increased risk of developing the condition. Additionally, certain infections may also be related.

Symptoms of AS

Typical symptoms of ankylosing spondylitis include lower back pain and stiffness. These symptoms may improve after movement, exercise, or a hot shower. Other symptoms include pain and swelling in neck, hips, knees, or ankles; difficulty expanding the chest; and fatigue. Other parts of the body can also be affected.

Ankylosing spondylitis can get worse over time. Getting help from a doctor as soon as possible is important. The natural progression of AS involves stiffening of the spine over time, with fusion of all or some of the spinal joints occurring after some years of disease in about two thirds of patients.

Treating AS

There is no cure for ankylosing spondylitis, but many treatments can help. Many people start with over-the-counter drugs and prescription pain relievers and anti-inflammatory drugs. Your doctor may also prescribe an individualized exercise program. These treatments can help manage symptoms of AS, like pain.

Your doctor may also try other medications that work on the immune system to treat inflammation and manage symptoms. In many patients, the biologic medicine ENBREL can help manage symptoms associated with AS. Read about results with ENBREL.

ENBREL is a prescription medicine that is self-injected. Because ENBREL works on your immune system, it may lower your ability to fight infections and may raise other safety concerns. If you have any sign of an infection including a fever, cough, flu-like symptoms, or have any open sores on your body, call your doctor. Please see Prescribing Information, Important Safety Information, and Medication Guide for complete details about ENBREL.

Prescription ENBREL is taken by injection.


Ankylosing Spondylitis (AS)
ENBREL is indicated for reducing signs and symptoms in patients with active ankylosing spondylitis.

Supportive data
Ankylosing Spondylitis (AS)
  • ENBREL was shown to be effective in about 3 out of 5 adults at 6 months. Clinical responses were seen at 2 weeks in 46% of patients, with 59% of patients receiving benefit within 8 weeks.
How do I know if I have AS?

Before your next appointment with your doctor, download these questions to help guide your conversation.

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