Its president, Dr Subramaniam Muniandy, said the oxygen canisters should only be given under strict advice and supervision by registered medical practitioners, adding that it was also a fire hazard.

“MMA is deeply concerned over the widespread advertising of oxygen supplementation canisters, which supply 99% of pure oxygen for home use.

“In one advertisement, a company even highlights that the product has been approved by the health ministry and indicated that oxygen supplementation is safe for children.”

Citing Dr Victor Hoe, a professor of occupational and public health from Universiti Malaya, Subramaniam noted that with the Covid-19 pandemic, many people were trying to supplement atmospheric oxygen that they breathe, with either oxygen concentrators or canister oxygen.

He said it was important for the public to understand that all Covid-19 patients using an oxygen concentrator or canister oxygen under home isolation should be closely monitored by healthcare workers.

If any deterioration is detected in the partial pressure of oxygen, the person should be admitted to a hospital for further assessment and treatment.

Subramanian said home-use oxygen supplementation should only be prescribed to patients with a low, partial oxygen pressure due to a chronic lung or heart condition.

“It should only be given in a controlled amount as excessive oxygen is not beneficial and can be toxic to a patient.

“There are many complications that arise from breathing pure oxygen for a prolonged period of time.

“Also, the oxygen coming out from the canister is cold and dry. It needs to be conditioned before we can breathe it.

“Breathing cold and dry air can damage the lungs and increase the risk for us to get lung infection.”