How To Reduce Post Herpatic Neuroalgia?

my mother is a leukemic patient and she is receiving chemotherapy ,her next chemotherapy dose will be within three days what concerns me that she she have shingels out brake in her hands for 2 weeks and didnt heal yet, i m afraid that she develops post herpetic neuroalgia .she is taking acyclovir 400 mg every 6 hrs and 1 laryica 75 mg pregablin at night for the pain whichis not enough for her night pain

1.what can she take for her nigh pain

2.how to reduse post herpatic neuroalgea