Gastrointestinal symptoms, including diarrhoea and abdominal pain, are one of the earliest and most frequently reported signs of Fabry disease, a rare X-linked lipid storage disorder. As the disease progresses, renal, cardiac and cerebrovascular complications develop, resulting in more serious symptoms and early mortality. The present study evaluated the effects of enzyme replacement therapy (ERT) with agalsidase alfa on the gastrointestinal symptoms of Fabry disease. Following 6 months of treatment, both the severity ( p < 0.02) and frequency ( p < 0.02) of abdominal pain decreased. For those patients who had received agalsidase alfa for more than 6 months, the observed improvement was generally maintained. This is the first study indicating a significant beneficial effect of ERT on gastrointestinal symptoms in a group of patients treated for Fabry disease.