Chronic fatigue syndrome (CFS) is a disabling, unexplained disorder characterized by physical
and mental exhaustion. Complaints of disturbed and unrefreshing sleep are very common in CFS
patients, however, the relationship between (disturbed) sleep quality and fatigue is still
not fully elucidated. To evaluate the effect of sodium oxybate on fatigue and to explore the
interdependence of sleep quality and fatigue in CFS, a double blind, randomized, placebo
controlled cross-over trial with sodium oxybate is carried out in CFS patients.
The aim of this study is to address the issue of the effect of sodium oxybate on fatigue as a
presenting symptom in chronic fatigue (CF) and CFS patients, in the absence of underlying
medical or psychiatric illness. The answer to this question may shed further light on the
enigmatic relationship between sleep and fatigue. We also want to investigate the effect of
sodium oxybate on sleepiness and general health in the same target population.
Zero-hypothesis: there is no effect.