We report on acute painful neuropathy following reduction of high serum glucose levels in six diabetic patients, aged 27–52 (5 males). Initial glucose levels ranging between 270 and 600mg/dL decreased to 60–160mg/dL following insulin, pharmacologic or dietary treatment. Four patients had long-standing untreated diabetes (3–5 years). All six patients experienced severe excruciating neuropathic pain 2–4 weeks after initiation of treatment. Pain was generalized in all, starting in the feet in 4 cases. Pain intensity prompted the use of combination therapy with various anti-neuropathic pain agents. Symptoms gradually improved in all patients, allowing discontinuation of symptomatic therapy within 3–8 months. We conclude that acute painful neuropathy can complicate the correction of high glucose levels in diabetic patients. Therefore, careful correction of glucose levels should be considered in patients with long-standing uncontrolled diabetes.