We report a 53-year-old man with sero-negative rheumatoid arthritis who developed a fever, rash and hepatitis 3 weeks after starting sulphasalazine therapy. This was associated with a T cell lymphocytosis, eosinophilia and evidence of classical complement pathway activation. He responded to high dose corticosteroids. This is a rare but characteristic reaction which is likely to be encountered by rheumatologists more frequently with the increasing use of sulphasalazine. It should be recognized promptly as it may be fatal and can be confused with other systemic diseases.