Rabbi Blumenkrantz’ book is different, because he recommended against certain medications. Nothing’s going to happen to you if you eat kishka instead of pizza on Motzaei Shabbos.
Regardless, everyone should ask their own rav, and not rely on any book of that nature (unless your rav tells you that you should). If anyone doesn’t take their medication without first discussing it with their own rav, it’s their own foolishness.