Authorities in  Lagos said on Friday that hospitals had seen cases of chloroquine poisoning after US President Donald Trump touted the drug as a treatment against the coronavirus.

Trump said during a press conference on Thursday that the antimalarial drug had been “approved” to treat Covid-19 by the US Food and Drug Administration, only for the head of the agency to push back and say it had not yet been given a definitive green light.

The drug has recently been used to treat coronavirus patients in China and in France, where some researchers said it showed great promise, though scientists agree that only more trials would determine if it really works and is safe.

Health officials in Lagos said that there had already been claims online pushing chloroquine as a treatment and that Trump’s message had seen interest surge.

In the last few days, we’ve seen a lot of messages going around on social media about chloroquine being a cure for coronavirus and in some parts of Lagos, it was no longer available,” said Ore Awokoya, senior special assistant to the Lagos state governor on health.

“But after Donald Trump’s statement it took another dimension, people were massively queuing in front of the pharmacies to buy chloroquine.”

She describe the rush to take the drug as “worrying” given that people were “self-medicating without any sort of guidance”.