Twitter has barred US president’s eldest son from tweeting for 12 hours.
The punishment came after a post by Donald Trump Jr contained a video discussing the benefits of Hydroxychloroquine.
Some, including President Trump, have suggested the drug works as a preventative measure against coronavirus, despite medical studies that indicate the contrary.
Twitter said the post had violated its Covid-19 misinformation rules.
Donald Trump Jr will still be able to browse Twitter and send direct messages in the interim.
A spokesperson for Donald Trump Jr said the decision had been “beyond the pale”.
“Twitter suspending Don Jr for sharing a viral video of medical professionals discussing their views on Hydroxychloroquine is further proof that big tech is intent on killing free expression online, and is another instance of them committing election interference to stifle Republican voices,” Andy Surabian said.
“While there is indeed much disagreement in the medical community about the efficacy of Hydroxychloroquine in treating coronavirus, there have been studies reported by mainstream outlets like CNN, suggesting that it may in fact by an effective treatment.
“Those pretending otherwise are lying for political reasons.”
The ban comes weeks after President Trump asked the National Telecommunications and Information Administration to file a petition to look at how social media companies moderate content.
The petition asks the Federal Communications Commission to reconsider rules that shield social media providers from liability for content posted by their users, but still let them remove posts they deem to be objectionable.