Amazon has banned more than one million products which claim to protect against the coronavirus - or even cure it.
The online retailer told Reuters it had also removed "tens of thousands" of overpriced health products from unscrupulous sellers.
The World Health Organisation (WHO) expressed concern about some misleading Amazon listings earlier this month, including fake treatments.
The virus, which causes Covid-19, has killed about 2,800 people worldwide.
The WHO said fake coronavirus claims online were causing mass confusion, and urged tech giants to combat the spread of misinformation.
A search for "coronavirus" on Amazon brought up results for face masks, disinfectant wipes and newly-published books on viral infections, revealing how some sellers are cashing in on the health crisis.
It also offered results for vitamin C boosters - a fake cure for the virus that has been widely disseminated online.
Amazon has not provided a list of those products it says it has removed, but a BBC search for "coronavirus" on the online site suggests many products are still being sold at unusually high prices.
In one example, a 50-piece stack of surgical masks from one seller cost more than £170, while a popular alternative of the same product is on sale for approximately £36. Even that cheaper product has still risen dramatically in price since early January, when it cost less than £10.
Some of those products are not even fit for purpose, such as disposable dust or surgical masks, rather than recommended protective equipment.
New listings on Amazon explicitly market basic masks as "anti virus" or "for coronavirus"
A three-pack of a popular brand of hand sanitising gel cost between £10-15 until early January, when it soared to £50. It now sells for just over £30.
"There is no place for price gouging on Amazon," a spokeswoman told Reuters, referring to the practice of hiking up prices of goods to unreasonably high levels because of an increase in demand.
She cited company policy which allow Amazon to take down products that "hurt customer trust", including when pricing "is significantly higher than recent prices offered on or off Amazon".
The company will continue to monitor the site for price spikes, she added.