How to stop scew from working loose?

thor

I bought a swivel twin lever kitchen sink mixer tap and have found that one of the lever handles is very loose. So I tightened the screw which was fastening it to the rest of the bloc and that worked for a while but after a few hours of use the problem returned with the screw loosening again. It looks like the act of turning the lever also loosens the screw holding it. Any solutions how I can fix this?

Bradden

Medium strength Threadlok would be my suggestion.

donemedosh

Yes threadlok is one solution but does the screw have a locking washer if not I would fit one. Or it may need a new washer.