- patients treated with systemic ozone in the last 6 months - patients treated before with systemic ozone and referring any side effect - glucose-6-phosphate-dehydrogenase deficit - other severe concomitant disease apart from covid19 - psychiatric disease specified in axis i of l diagnostic and statistical manual of mental disorders, 5 edition, but major depression - patients not capable of understanding the study methods and targets - pregnant woman

- patients treated with systemic ozone in the last 6 months - patients treated before with systemic ozone and referring any side effect - glucose-6-phosphate-dehydrogenase deficit - other severe concomitant disease apart from covid19 - psychiatric disease specified in axis i of l diagnostic and statistical manual of mental disorders, 5 edition, but major depression - patients not capable of understanding the study methods and targets - pregnant woman