INTRODUCTION: Povidone-iodine and hydrogen peroxide could be effective in against SARS-CoV-2. METHODS: A “non-interventional trial” in 88 patients (43 ± 17 yrs, 55% men) with SARS-CoV-2 in nasopharyngeal swabs (RT-PCR). 31 received mouth rinses/gargling with povidone-iodine (every 8 h, two consecutive days), 17 with mouth rinses/gargling of hydrogen peroxide, and 40 controls. PCR were repeated at 3, 11 and 17 days. RESULTS: After intervention the viral load (Log 10 copies/ml) remained similar in povidone-iodine (4.3 ± 2.7 copies/ml), hydrogen peroxide (4.6 ± 2.9 copies/ml; p = 0.40) and controls (4.4 ± 3.0 copies/ml). The percentage of patients with a negative result in the second PCR was 27% in povidone-iodine group, 23% in hydrogen peroxide and 32% in controls; in the third PCR, 62%, 54% and 58% respectively; and in the fourth PCR, 81%, 75% and 81%. CONCLUSION: Our results do not support the clinical usefulness of mouth rinses/gargling with povidone-iodine or hydrogen peroxide in patients with COVID-19.