There are an astounding number of diet pills on the market today that promise quick or intense weight loss. Xenical – a prescription weight loss drug with Orlistat as the main ingredient – is one medication that was accepted by the U.S. Food and Drug Administration for the treatment of obesity. The over-the-counter version, Alli, was also FDA approved.

Orlistat is the generic drug that is in both these medications, though Xenical contains nearly twice the amount as Alli. Orlistat has been proven to help with weight loss, as part of a low calorie, high exercise routine, but it also has serious and dangerous side effects that caused the FDA to rethink its approval of the drug.

How Orlistat Works

Orlistat works by blocking the body’s absorption of fats found in the food ingested. It prevents the enzyme lipase from breaking down the fat, which keeps the body from soaking it up. The drug can block as much as 25 percent of fat from a consumed meal.

This is then passed through the body as stool. Because Orlistat also blocks the body from receiving certain vitamins normally obtained through food, multivitamin tablets need to be taken with the drug.

However, it can help improve high blood pressure caused by obesity as well as prevent Type-II diabetes. By blocking fat from being absorbed by the body, Orlistat can help with obesity and other health problems being overweight causes.

Gastrointestinal Side Effects of Orlistat

Unfortunately, the drug comes with potentially dangerous side effects. The most common side effects of Orlistat are gastrointestinal disorders.

These issues include, but are not limited to:

  • oily spotting,
  • flatus with discharge,
  • fecal urgency,
  • fatty or oily stool,
  • oily evacuation,
  • increased defecation,
  • fecal incontinence,
  • abdominal pain and discomfort,
  • nausea,
  • infectious diarrhea,
  • rectal pain and discomfort,
  • tooth disorder,
  • gingival disorder,
  • and vomiting.

There has also been at least one reported case of constipation.

Additional Side Effects

Back pains, headaches, and disrupted menstrual cycles have also been reported. Users suffering from gastrointestinal complications due to the drug usually only experience these effects for about a week upon starting dosage of Orlistat. Few have had these issues for more than four weeks. Most users found that upon discontinuing use of the drug, the side effects subsided within a day or two. Orlistat may lead to more serious health issues as well.

FDA Concern and Warning

The FDA began its investigation of the drug after it received several cases of liver-related problems. From 1999, when Xenical was approved as prescription to aid weight loss in obese patients, to 2008, 32 cases of serious liver injury, failure, and death caused by these complications were reported. A new warning was issued in May 2010 with the over-the-counter brand Alli, which contains orlistat, explaining these liver-related side effects.

Manufacturer Legal Liability

The companies that produce and market Xenical and Alli, Roche and GlaxoSmithKline, are currently facing potential individual lawsuits from users of the drug who experienced adverse side effects of the liver. Many lawyers are actively seeking clients to form individual litigations, often by providing free consultations. For those who have suffered liver injury or failure after taking either Xenical or Alli, a lawsuit may secure compensation for medical expenses and lost earnings.