Right indictator switching itself on

For the past few days, whilst driving the right sided indictator switches itself on or wont switch on at all. I am not sure if the indictator lever on the steering column has become hypersensitive. Or related to the movement in the steering wheel itself Its Becoming quite dangerous. I have checked the bulbs in the headlights and some of the smaller bulbs have gone but these have been replaced but the problem still remains. It flutuates between being relentless but just switching itself on occasionally. Help please !!