A new study shows the maximum safe dose of ivermectin still does not help treat COVID-19. 

Ivermectin is a common medication used to treat parasitic infections in humans and animals, and it is very effective for this purpose. 

However, there have been claims (largely among fringe groups) that the drug may also be effective in treating COVID-19, and was somehow suppressed as a treatment option in favour of vaccination. 

The promotion of ivermectin as a COVID-19 treatment has been based on small studies and anecdotal evidence, rather than large randomised controlled trials.

Some studies suggest that ivermectin may have antiviral effects in a laboratory setting and may reduce the severity of COVID-19 symptoms, but these results have not been consistently replicated in larger studies.

Despite the lack of solid scientific evidence, ivermectin has been heavily promoted as a COVID-19 treatment, leading  to the widespread use of the drug in some regions, against the warnings of health organisations, including the World Health Organization (WHO), the US Food and Drug Administration (FDA), and the European Medicines Agency (EMA).

A new study from Duke university again shows why this line of treatment is unhelpful. 

The research found that taking the highest possible safe dose of ivermectin does not help treat mild to moderate COVID-19.

The researchers randomly assigned 600 people with mild to moderate symptomatic COVID-19 to receive 600 micrograms per kilogram of ivermectin, and 600 were given a placebo for six days. 

The researchers say there was no improvement in how quickly the ivermectin group recovered compared to the placebo group, meaning the highest dose that humans can safely tolerate is not effective to treat COVID-19.

The full study is accessible here.