Prealbumin FS is an immunoturbidimetric test to determine prealbumin in human serum und plasma. Prealbumin concentration decreases in the presence of inflammation, in the immediate postsurgical period, in protein malnutrition and in COVID-19 patients. Serum prealbumin levels may rise due to glucocorticoids, anabolic steroid and androgen use as well as in case of acute alcohol intoxication.