Does sulfasalazine work to treat ankylosing spondylitis and how safe is it?
To answer this question, scientists found and analyzed 11 research studies. These studies included almost 900 people with ankylosing spondylitis, most of them were male and 27 to 46 years old. People were either given sulfasalazine at 2-3 g per day or were in another group that had a fake pill for 12 weeks to 3 years. This Cochrane review provides the best evidence we have today.
What is ankylosing spondylitis and why is sulfasalazine prescribed?
Ankylosing spondylitis (AS) is a type of arthritis usually in the joints and ligaments of the spine. It may also affect shoulders, hips, or other joints and cause tendonitis. Pain and stiffness occurs and limits movement in the back and affected joints. It can come and go, last for long periods, and be quite severe. Non-steroidal anti-inflammatory drugs (NSAIDs) are the main treatment for AS and can improve the symptoms of AS. But when NSAIDs are not working well disease modifying anti-rheumatic drugs (DMARDs), such as sulfasalazine may be used. Side effects have been reported with sulfasalazine. Therefore, it is necessary to know how well sulfasalazine works and whether it is safe.
How well does it work?
Morning stiffness and the erythrocyte sedimentation rate/'sed' rate (ESR) decreased more in people taking sulfasalazine compared to those taking fake pills (lower ESRs usually mean less inflammation).
Morning stiffness decreased by 14 more points on a scale of 0 to 100 when taking sulfasalazine than fake pills.
Improvements in movement of the spine, pain, function (physical ability) and overall-well being was about the same whether people took sulfasalazine or fake pills. But one study found that improvement did occur in people who had not had AS for very long, who had very active disease or peripheral arthritis (arthritis in arms and legs).
How safe is it?
People had side effects such as stomach upset, skin reactions/rashes and mouth sores.
More people stopped taking sulfasalazine because of the side effects than when taking fake pills.
14 out of 100 people stopped taking sulfasalazine because of the side effects.
9 out of 100 people stopped taking fake pills
What is the bottom line?
There is "gold" level of evidence that sulfasalazine improves morning stiffness and the erythrocyte sedimentation rate (ESR) in people with ankylosing spondylitis. It is not clear whether it improves pain, function (physical ability), movement of the spine and overall well being.
Side effects occur in some people and include stomach upset, skin rashes and mouth sores which may occasionally stop people from taking sulfasalazine. But severe side effects appear rare.
People with early ankylosing spondylitis, with active disease or peripheral arthritis may improve with sulfasalazine.