GlycoPrep-C is a medical preparation used for bowel cleansing prior to procedures such as colonoscopy. It typically contains polyethylene glycol (PEG) along with electrolytes, which help to clear the intestines by inducing a watery diarrhea. This preparation is essential for ensuring that the colon is clean for optimal visualization during diagnostic procedures. As always, it's important for patients to follow their healthcare provider's instructions when using such preparations.