Ankylosing spondylitis symptoms
Ankylosing spondylitis (AS), now often called axial spondyloarthritis, is an inflammatory arthritis that mainly affects the spine and sacroiliac joints. It usually starts before age 45.
Common symptoms of ankylosing spondylitis
- Lower back and buttock pain that improves with activity, worsens with rest
- Morning stiffness lasting more than 30 minutes
- Pain that wakes you in the second half of the night
- Reduced spinal flexibility (bending forward, side-bending, rotation)
- Chest tightness from rib-joint involvement
- Heel pain, eye inflammation (uveitis), or fatigue in some people
When to see your GP
See your GP if you've had back pain for more than three months that improves with movement and worsens with rest — this is a recognised red flag for inflammatory back pain.
This is general information, not a substitute for personalised medical advice.
Frequently asked questions
What are the first signs of ankylosing spondylitis?
The earliest signs of ankylosing spondylitis often include joint pain, stiffness — particularly in the morning or after rest — and reduced flexibility in the affected area. Symptoms typically develop gradually, so keep a short symptom diary and speak to your GP if pain persists for more than a few weeks.
How is ankylosing spondylitis diagnosed in the UK?
In the UK, GPs diagnose ankylosing spondylitis from your symptoms, a clinical examination, and — where appropriate — blood tests, X-rays, ultrasound or MRI. For inflammatory types, your GP may refer you to UK healthcare rheumatology for specialist review under NICE guidance.
Can as symptoms come and go?
Yes. Many people with as experience flares — periods of worse pain, swelling and stiffness — followed by quieter spells. Tracking your flares helps you and your GP spot triggers and adjust treatment.
When should I see a GP about ankylosing spondylitis symptoms?
Book a GP appointment if joint pain has lasted more than a few weeks, is interfering with sleep or daily life, or is accompanied by swelling, warmth, locking or unexplained fatigue. Early assessment leads to better long-term outcomes.
Is ankylosing spondylitis the same as general arthritis pain?
No — there are over 100 forms of arthritis, and ankylosing spondylitis has its own pattern of symptoms, affected joints and treatment pathway. Getting the right diagnosis matters because the most effective treatments differ between conditions.