As coronavirus cases surge across the US, the Food & Drug Administration (FDA) has warned against buying or using an oxygen concentrator at home without a valid prescription as it could lead to serious health problems such as oxygen toxicity.

Oxygen concentrators are medical devices required to be sold and used only with a prescription.

The FDA said it was aware of some oxygen concentrators being sold online without a prescription and stressed it had not “approved or cleared” any oxygen concentrators to to be sold or used without a prescription.

“You should not to use an oxygen concentrator at home unless it has been prescribed by a health care provider,” the FDA said in a statement.

“Giving yourself oxygen without talking to a doctor first may do more harm than good. You may end up taking too much or too little oxygen.”

“Deciding to use an oxygen concentrator without a prescription can lead to serious health problems such as oxygen toxicity caused by receiving too much oxygen. 

“It can also lead to a delay in receiving treatment for serious conditions like Covid-19.”