Orlistat or Xenical is indicated for weight loss.
Orlistat or Xenical is a lipase inhibitor. Lipase is an enzyme found in the bowel which assists in lipid or fat absorption by the body. Orlistat or Xenical blocks this enzyme reducing the amount of fat the body absorbs - by about 30%. It is known colloquially as a "fat blocker".
Because more dietary fat is left in the bowel to be excreted, Orlistat or Xenical can cause an oily anal leakage and fecal incontinence.
People with bowel conditions such as irritable bowel syndrome or Crohn's disease may not be able to use Orlistat or Xenical.
Orlistat or Xenical can affect the way other drugs are absorbed because it affects the bowel contents.
FDC Reports 1997;59(20):3
Int J Obes 1993;17:241
J Clin Pharmacol 1996;36:152
The relevant product monographs must be regarded as the appropriate sources of prescribing information.