text: Feasibility of Vitamin C in the Treatment of Post Viral Fatigue with Focus on Long COVID Based on a Systematic Review of IV Vitamin C on Fatigue Fatigue is common not only in cancer patients but also after viral and other infections Effective treatment options are still very rare Therefore the present knowledge on the pathophysiology of fatigue and the potential positive impact of treatment with vitamin C is illustrated Additionally the effectiveness of high dose IV vitamin C in fatigue resulting from various diseases was assessed by a systematic literature review in order to assess the feasibility of vitamin C in post viral especially in long COVID fatigue Nine clinical studies with 720 participants were identified Three of the four controlled trials observed a significant decrease in fatigue scores in the vitamin C group compared to the control group Four of the five observational or before and after studies observed a significant reduction in pre post levels of fatigue Attendant symptoms of fatigue such as sleep disturbances lack of concentration depression and pain were also frequently alleviated Oxidative stress inflammation and circulatory disorders which are important contributors to fatigue are also discussed in long COVID fatigue Thus the antioxidant anti inflammatory endothelial restoring and immunomodulatory effects of high dose IV vitamin C might be a suitable treatment option 