Thanks Kate. Sorry no reply for a while, but t took a long time to work it all out with my meds and fix the neutropenia. The Big 3 can cause neutropenia -- especially Ethambutol -- but there are treatments to help.
In my case it turned out to be one of the blood pressure meds I am on and we've stopped that. So far, the neutropenia has gone.
(PS. As we get older more people develop reactions to drugs, even the ones they've been on for a while. I've also had to stop all Statins for cholesterol because I now get hypersensitivity vasculitis rash from them).