My Sister Was Diagnosed 20 Years Ago,started Medication After 4years

My sister was diagnosed 20 years ago,started medication after 4years ,been doing great but for the last 4years been growing increasingly lean especially on the face,arms and legs. Its so worryingly, but her doctors don't seem to do nothing about it . Please is there something she can take in addition to her medication? She is on 3 medication a day, i only remember kivexa and efivarenz. Your advice is much appreciated, thanks