JOHN1 - I would request P&T, as soon as possible. Actually once the claimant is 55yo or over they should be rated P&T (ie: no future exams). Applying for TDIU is an application for increase and therefore the VA will probably do a re-examination, as they like to have something to fall back on, that supports their decision, either way. Yes, they could reduce, however it's highly unlikely they would do it and it's usually an easy win to stop the reduction.
If it's been more than one yr, since your 100% award, you could also CUE that decision, stating that they failed to award you P&T, as required by VA policy. That could bring you a retro active award of P&T and ChampVA(if you have some medical bills either paid for or still owed, for that previous two yrs). Also, did they consider A&A or Housebound(HB) in that decision?? If not they should have and I would pursue that, if you feel that it's appropriate. Just a few thoughts.
As to your medications, you are not required to take any and whether you do or not should not have any affect/effect on your claim. I've taken meds for my 100% PTSD three times, for about three months, in the 22+yrs I've had my 100% award. jmo
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