I have been an asthmatic for 45 years ... well-controlled for most of that time. For a period of 2 years, I struggled with lung infections and excess mucous production to the point where It was one of the reasons I retired early.
A visit to my doctor after my last round of antibiotics suggested that the causative agent for infection was Haemophilus influenzae, a bacteria that he thought my immune system should be able to manage.
I continued to get sore throats, coughed most of the day, and produced an excessive amount of mucous every day.
After seeing some stories on anti-bacterial gargling for protection against upper respiratory infections during the COVID outbreak I embarked on the use of gargling with mouthwash every day.
Presto - coughing reduced to 5% (i.e. normal levels associated with asthma) and no more heavy coloured mucous production. No more infections.
Fantastic. Life is different now. Also, I reduced my asthma medication to 1/2 of the previous level.