A double blind randomized controlled trial was conducted in 71 adolescents aged 11-18 years. Inclusion in the trial required fulfilment of the diagnostic criteria, (Fukuda et al., 1994). Three infusions of 1 gm/kg (max 1 litre of 6 gm/100 ml in 10% w/v maltose solution) were given one month apart. The dummy solution was a 10% w/v maltose solution with 1% albumin of equivalent volume for weight. Efficacy was assessed by difference in a mean functional score including school attendance, school work, social activity and physical activity, between baseline, three months and six months after the final infusion. There was a significant mean functional improvement at the six month follow-up of 70 adolescents with Chronic Fatigue Syndrome of average duration 18 months. There was also a significant improvement for both groups from the beginning of the trial to the six month post infusion follow-up. Adverse effects were common with both solutions but not predictive of response. Neither solution could be identified by recipients.