Vascular dysfunction, including impaired perfusion has a pivotal role in the pathogenesis of microvascular complications in diabetes mellitus. Both pentoxifylline (PF) and pentosan polysulphate (PPS) are known to improve microcirculation. Antioxidant and antiproteinuric effects of PF are also known. In a placebo-controlled study, we determined the possible efficacy of PF-PPS combination therapy on diabetic neuropathy and nephropathy in type 2 diabetic patients. Patients in Verum group (n = 77) received PF-PPS infusions (100-100 mg/day) for 5 days. Control diabetics (Placebo group; n = 12) were given only saline infusions. Specialized cardiovascular autonomic reflex tests, vibration threshold values and urinary albumin excretion were assessed before and after therapy. In Verum group, autonomic score, indicating the severity of cardiac autonomic dysfunction, decreased after therapy (p < or = 0.001). Of the reflexes, deep breath and handgrip tests also improved after therapy (p < or = 0.001). Vibration threshold values, an indicator of the loss of sensory nerve function, were increased after therapy (p < or = 0.001). Results of cardiac autonomic tests and vibration threshold values remained unaltered in Placebo group. Majority of patients had normalbuminuria, which was not affected by PF-PPS. In conclusion, short-term PF-PPS therapy was effective on cardiovascular autonomic function and vibration perception, whereas it failed to reduce albuminuria within normal range in type 2 diabetic patients.