We know ozone is bad for our lungs – the increased risk of developing diseases such as asthma was one of the reasons people wore face masks during January’s record-breaking smog in China. But ...

In lung-injured animals, sildenafil also reduced mean pulmonary artery pressure and PVR by 30%. Again, this effect was achieved at the lowest dose, without subsequent changes at higher doses.

Impaired gas exchange in COPD can cause symptoms like shortness of breath, coughing, and fatigue. It also leads to hypoxemia and hypercapnia.