Gargling with Iodine











This paper remains the property

of the authors.

Paper Conclusion

This preliminary study showed that gargling with

1% PVP-I and essential oils show great potential

to be part of the treatment and management of

Stage 1 COVID-19

[This is a preprint paper - Preprints are studies

destined for peer-reviewed journals that have

yet to be peer-reviewed. Because COVID-19 is

such a rapidly evolving disease and peer-review

takes so long, most of the information circulating

about the disease comes from preprints.]

Please download the full paper below:


Study link here

Summary of design and results

20 asymptomatic or pre-symptomatic COVID-19

patients from a Malaysian university hospital were

randomly allocated into four groups:

--Group A gargled with 10 milliliters of 1%

povidone-iodine for 30 seconds, three times per day.

--Group B did the same with 20 milliliters of Listerine.

--Group C did the same thing with 100 milliliters of

tap water.

--Group D acted as untreated controls.

The patients ranged in age from 22 to 56, had positive

PCR tests for COVID-19 but hadn't developed any

symptoms yet, were enrolled within 5 days of being tested,

and did not receive any other treatments.

Two patients had co-morbidities: one had asthma and one

had obesity. Unfortunately, they didn't report which groups

these two patients were in.

On day 4, 100% of those in the povidone-iodine group had

cleared the virus. By contrast, 80% of those in the Listerine

group, 40% of those in the tap water group, and 20% of those

in the control group had cleared the virus.

The one patient in the Listerine group who had not cleared

the virus on day 4 was still positive on day 6 and was

indeterminate on day 12.

Of the three patients who remained positive on day 4 in the

tap water group, two became indeterminate on day 6, but

one of them slipped back into positive by day 12. No one

who wasn't negative on day 4 cleared the virus by day 12.

In the control group, one person tested negative on day 4, but slipped into the positive or indeterminate territory by day 6. On day 12, still only one person tested negative.

Due to its small size, the study did not have the statistical power to compare every group. However, the difference between the povidone-iodine group and the control group was statistically significant at every day.

This study is small and was not blinded. Further studies will be needed to test this in larger samples, different populations, and to see if this treatment is effective in more serious cases where symptoms or complications have developed.


Nevertheless, it provides preliminary results suggesting that gargling with povidone-iodine and Listerine can both help clear the virus, and that povidone-iodine is most effective.