Dr Hilary Jones hit out at the use of hydroxychloroquine after President Trump confessed that he was taking the unproven anti-malaria drug.
The doctor, 66, warned that there were a number of troubling consequences of using the drug, including heart failure.
He also said that there were no benefits found in the clinical trials and that Trump was "three weeks behind on the rumour mill".
Dr Hilary went further to suggest that Trump "sounded like a drug pusher" by telling US citizens that they "might like" the drugs.
Asked by Susanna Reid about his opinion on Trump's confession, he said: "It can be very toxic. I have to say, it's better than intravenous bleach."
Listing the drug's potential harmful effects, he said: "It can cause heart failure, very toxic to the liver so therefore there are no benefits shown in the clinical trials. In fact, it could be dangerous."
"It's quite a toxic drug, it needs to be used very carefully," Dr Hilary continued. "But there is no proven evidence."
Yesterday, Trump said that he has taken a pill a day for around ten days after his doctor offered him a prescription.
Speaking at a meeting in the White House, Trump said he has been having "zero symptoms".
He also revealed that he is getting tested for Covid-19 daily but claims he has not been exposed to the virus.
Trump previously suggested that it could be used in the fight against coronavirus, despite little scientific evidence to support his claims.
People around the world use decades-old hydroxychloroquine to treat malaria as well as inflammatory conditions like lupus and rheumatoid arthritis.
But researchers are seeing occasional cases of coronavirus infection in these patients despite long-term use of the drug.
*Good Morning Britain airs weekdays at 6am on ITV
