Whats the best treatment for persistent cold related cough?

No cure: Assuming no other cause for ongoing cough: Post-viral cough can persist for many weeks.Also we are experiencing an epidemic of the '100 day cough' (Whooping Cough). Your age group is considered to be the vector for this infection and also, there is no cure. Cough syrups containing pholcodeine (available over the counter) may give you some slight symptomatic relief but are not really very effective

Get checked: May be wise depending on your history to get carefully checked by GP. While cough may be postviral, asthma, other lung pathology and reflux, medication effects may need to be excluded in some circumstances and may need consideration of X-ray and spirometry (lung function test). If postviral cough is the diagnosis unfortunately the treatment for that is time as Dr McQuade has said.

Cough : Cold is a viral infection. Sometimes we can get post viral cough which can persist for long . Mostly it settles on its own but if it’s too annoying see doctor. Another important thing to think is possibility of pertussis infection which is a bacterial infection. . Best to see doctor .