Rituximab is a chimeric monoclonal antibody that targets CD20 antigen at the surface of B lymphocytes. The efficacy of rituximab in patients with rheumatoid arthritis has been demonstrated in 3 randomized controlled trials. Rituximab is now used in a wide range of systemic autoimmune and inflammatory diseases, as it is well tolerated and efficient. Adverse events are scarce, consisting mainly in reactions during infusion and infectious complications that are favoured by the association of rituximab therapy with other immunosuppressants. Relapses of the disease are common around six months after rituximab infusion. The response to retreatment with rituximab is usually the same that was obtained after the first course of treatment.