IRCT20220814055690N1 IRCT 2024-03-22 Bagheiat-allah University of Medical Sciences Effect of ozone therapy in post COVID-19 lung sequels Investigating the consequences of ozone therapy in hypoxia of oxygen-dependent patients affected by COVID-19 after discharge from the hospital 2024-04-03 anticipated 206 Complete https://irct.ir/trial/65280 interventional Randomization: Randomized, Blinding: Not blinded, Placebo: Not used, Assignment: Parallel, Purpose: Treatment, Randomization description: Permuted (block randomization). Based on this method, the patients are categorized and equal number of participants are entered into the intervention and control groups at consecutive but equal time intervals. In this way, for example, one type of treatment is given to the first block, another type is given to the second, and again the first type is given to the third block and so on. N/A Condition 1: Post COVID fibrosis/ inflammatory lung disease. Condition 2: COVID-19 disease. Intervention 1: Intervention group: Patients referred to ozone therapy centers affiliated to Baqiyatullah University located in Tehran and Najaf Abad, with a history of contracting COVID-19, who have been discharged from hospital with hypoxemia and oxygen dependency, will be included in the study. The therapeutic dose is 35-50 micrograms/mL with a volume of 120-240 cc of blood and its equivalent O2/O3 mixture for 5-20 sessions, based on the inflammatory factors and severity of lung involvement and hypoxia at the time of referral, the exact amount of the dose and the number of sessions is selected. The first sessions will be daily and then alternate in the week. Intervention 2: Control group: This group receives standard treatment including prednisolone or pirfenidone. These patients were admitted to the hospital and referred to the relevant medical centers and received appropriate treatment and were included in the study under the name of control group. Normally, the dose of Pirfenidon for the first week is 267 mg daily, for the second week, 534 mg, and from the third week (maintenance treatment) 801 mg. Maintenance treatment is selected based on the condition and severity of the patient's involvement. Prednisolone is usually 1mg/kg daily, which can be changedbased on the patient. No - There is not a plan to make this available Justification or reason for not sharing IPD is There is no further information