Conditions and symptoms
What Is Ankylosing Spondylitis? Plain-English Guide
Ankylosing spondylitis · say it: ang-kuh-LOH-sing spon-duh-LY-tisAlso written: AS, axial spondyloarthritis, Bechterew's disease
Short answer
Ankylosing spondylitis is a long-term inflammatory arthritis that mainly affects the spine and the joints where the spine meets the pelvis.
What it means
Ankylosing spondylitis (AS) is a type of inflammatory arthritis. It mainly affects the spine and the sacroiliac joints, where the lower spine joins the pelvis. A common early sign is lower back pain and stiffness that is worse after rest and in the morning, and improves with movement. Over many years, in some people, parts of the spine can stiffen.
AS appears on medicine labels mostly in the 'Indications' section. Some anti-inflammatory medicines and some medicines that act on the immune system are approved to treat it. Because some of these medicines can lower the body's defence against infection, their labels also carry warnings about infections.
AS is different from ordinary mechanical back pain, which usually gets worse with activity and better with rest. It is also different from rheumatoid arthritis, which more often starts in the small joints of the hands and feet.
Where you may see it
- The 'Indications and Usage' section of some anti-inflammatory and biologic medicine labels
- Rheumatology clinic letters
- Spine and pelvis X-ray or MRI reports that mention sacroiliitis
📄 How it looks on a report
Indicated for reducing signs and symptoms in adult patients with active ankylosing spondylitis.
🙅 What it does not mean
- Back pain alone does not mean ankylosing spondylitis. Most back pain is mechanical and has other causes.
- A medicine listing AS does not mean you have it. Labels list all the conditions a medicine is approved for.
- AS is not just a back problem. It can sometimes affect the eyes, other joints and the bowel, which is why doctors ask about these.
🗒️ Questions to ask your doctor
💊 Medicines whose labels mention “Ankylosing spondylitis”
Plain-English explanations of each medicine, from its official FDA label.
- Diclofenac Sodium
A nonsteroidal anti-inflammatory drug (NSAID). The FDA class is not listed on the label.
- Naproxen
a nonsteroidal anti-inflammatory drug (NSAID), which is a medicine that reduces pain, swelling, and inflammation
- Prednisolone
a corticosteroid, a type of steroid medicine. The label describes glucocorticoids as adrenocortical steroids, both naturally occurring and synthetic, that are readily absorbed from the stomach and intestines.
- Prednisone
a corticosteroid, a type of steroid medicine that works like the adrenocortical (adrenal gland) steroids the body makes naturally
🔗 Read more from trusted sources
- “Ankylosing spondylitis” on MedlinePlus ↗
US National Library of Medicine
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