Chen Shuying had been coughing for more than a week before she sought help at a new clinic for smog-related illnesses at the No 7 People's Hospital of Chengdu, Sichuan province, on Wednesday afternoon.

"Never before have I coughed for so long. The doctor confirmed my fears that my symptoms were brought on by the smog," the 79-year-old said.

Instead of prescribing antibiotics, a glucose drip or other kinds of medicine, the doctor gave her anti-allergy medicine and a bronchodilator, which dilates the air passages in the lungs, opening constricted airways. Both were prescribed in tablet form.