There have been concerns about the side effects of monoclonal antibodies, and specifically of infliximab, but these are rare. Early side effects include the risk of allergic reactions (including anaphylaxis which may be life-threatening), and reactions to the infusion. These are often treated with medications given before treatment. Infliximab also carries a risk of worsening infection, and can cause reactivation of old infections, like tuberculosis . Over time, there is the risk of serum sickness , which is a delayed hypersensitivity response to the medication. Later complications may include multiple sclerosis and lymphoma . Finally, the medication is quite expensive, with treatment costs ranging from US$3000 to $8000 per infusion.   
Treatment of IBD, including surgery, should always be the initial strategy to induce remission of peripheral arthritis. Nonsteroidal anti-inflammatory drugs are not recommended in patients with IBD because these agents may worsen IBD symptoms. Corticosteroids may be used orally or by local injection. Sulfasalazine and methotrexate may be helpful in some cases. Tumor necrosis factor antagonists, such as infliximab and adalimumab, are indicated to treat Ankylosing Spondylitis and IBD, and may be effective for other IBD spondyloarthritides.