What Could The Reasons Be For A Blood Pressure To

What could the reasons be for a blood pressure to drop to 50/30? My sister takes hyzar, xanax daily. She is somewhat of a heavy drinker for many years. Her abdomen seems large. She gets frequent nosebleeds. Recently she was told her liver enzymes were up. Also gets abdominal pain. After receiving iv fluids her pressure is back to normal.