 The aim of this long-term observational study is the documentation of the use of PASCORBIN 7.5 g in patients with vitamin C deficiency. Regarding the vitamin C deficiency, the investigators focus on the acquisition of data of the underlying diseases and the reduction of symptoms, that are related to oxidative stress and vitamin-C-deficiency. Next to this, exact assessment of medical tolerance and details of treatment requirements are further aims. Here the investigators take into account acute and chronic underlying medical conditions. Further health economic data are collected. 