constant throat clearing in the office

[lu_hawk]

there is a guy at work that clears his throat all day, every day. it annoys me extremely. and it makes it hard to concentrate on my work when he is doing it badly. when asked about it he says it is because of asthma.

so first question is can asthma cause you to need to clear your throat all day? i don't think it can but maybe somebody with asthma can tell me.

second question. assuming he doesn't have a valid medical excuse and this is just an annoying habit then what is the best course of action?