['Increased plasma tumour necrosis factor alpha (TNF) concentration correlates with mortality in sepsis. We suggested that pentoxifylline (PTXF), which is known to inhibit TNF production, may improve survival and attenuate clinical symptoms of sepsis in neonates. Plasma TNF levels were evaluated in 29 newborn infants with sepsis. Patients were randomly assigned into two groups, receiving PTXF in a dose of 5 mg/kg per hour for 6 h or placebo (saline), on 3 successive days. Both groups were subjected to the same conventional therapy. TNF was evaluated before and after PTXF or placebo administration on the 1st and 3rd days of therapy. There was a statistically significant decrease in plasma TNF level in the PTXF group when the values before the first and after the last PTXF infusion were compared [mean: 671.5 pg/ml; SD: 438; med: 729.6 vs mean: 41.0 pg/ml; SD: 64.1; med: 11.5; P < 0.000004]. In the placebo group, decrease was not significant [mean: 633.0 pg/ml SD: 488.6; med: 618.9 vs 246.9 pg/ml; SD: 243.9; med: 191.0]. A significantly higher plasma TNF level, evaluated after the last PTXF infusion, was found in the placebo group [246.9 pg/ml vs 41.0 pg/ml; P < 0.001]. Only one of four infants with signs of shock in the placebo group survived, whereas all of five newborns with symptoms of shock in the PTXF group survived [P < 0.04]. An increased incidence of metabolic acidosis [P < 0.05], necrotizing enterocolitis [P < 0.04] and renal insufficiency [P < 0.05] was observed in infants in the placebo group.'] Does pentoxifylline reduce plasma tumour necrosis factor-alpha concentration in premature infants with sepsis?