Treatment of Post-COVID-19 With Hyperbaric Oxygen Therapy: a Randomized, Controlled Trial

The goal of this clinical try is to investigate the effect of hyperbaric oxygen therapy (HBOT) on symptoms, quality of life and absence of work through sickness in patients with post-COVID on short- and mid-term, as well as to identify biochemical mechanisms of action. The main questions it aims to answer are: * What is the clinical relevance of improvements of symptoms and quality of life after treatment with HBOT for post-COVID? * What are the changes in absence from work after treatment with HBOT? * What is the cost-effectiveness of treatment with HBOT? * What are possible mechanisms of action of HBOT? Participants will undergo 40 sessions of HBOT. Researchers will compare HBOT with standard care alone (control group). In case of a positive outcome, patients in the control group can cross-over to the HBOT group after 6 months.