Graves’ disease is an autoimmune thyroid disorder and the most frequent cause of hyperthyroidism in Slovenia. Antithyroid drugs are usually used as the first line of treatment. However, in rare cases they cause agranulocytosis with life-threatening neutropenia. We present a case of a patient who was simultaneously diagnosed to have Graves’ disease as well as moderate neutropenia, which was most likely a consequence of recent gastroenteritis but could also be a consequence of untreated Graves’ disease. Due to severe hyperthyroidism, urgent treatment with antithyroid drugs was indicated. Given that the cause of neutropenia was recognized, we started intravenous treatment with thiamazole, with daily monitoring of leukocyte and granulocyte counts. In subsequent days, the granulocyte count recovered, the patient’s general state improved and she was able to continue treatment in an outpatient setting.