Fat blockers, or lipase inhibitors, help people lose weight by blocking the amount of fat that their bodies digest, according to the National Institute on Diabetes and Digestive and Kidney Diseases. The most commonly used lipase inhibitor is the drug orlistat, which in the United States is available as prescription Xenical or the over-the-counter formulation Alli.
Contraindictions
People under the age of 18 should not use fat blockers such as orlistat, warns PubMed Health. Women who are pregnant or nursing should also avoid orlistat. Anyone who has had an organ transplant, a serious medical problem such as high blood pressure, a compromised immune system, a history of eating disorders or substance abuse should also avoid orlistat. The fat blocker also interacts with some medications, including those prescribed for thyroid disease.
How Orlistat Works
Orlistat stops the digestive system from digesting fat consumed and eliminates the fat through bowel movements, according to the Mayo Clinic. But taking the fat blocker is not a license to go on an eating spree. People who eat more than 15 g of fat at a meal may experience uncontrollable bowel movements, oily stools, fatty stools, severe stomachaches, rectal pain and oily spotting onto their underwear. Generally, orlistat users take a pill before eating a meal; dieters can skip doses if they are eating a low-fat or fat-free meal or snack.
Additional Side Effects
Some dieters have alleged that their use of orlistat caused them severe liver injury, according to PubMed Health. Signs of serious liver injury include jaundice, dark-colored urine and light-colored stools. Some people may be allergic to fat blockers and need immediate emergency medical assistance if they suffer from itching, hives, rashes or difficulty breathing. Other potential side effects that usually do not constitute a medical emergency include headaches, anxiety and irregular menstrual periods.
Weight Loss Potential
Alli has 60 mg of orlistat per pill, while Xenical includes 120 mg of orlistat per dose, according to the Mayo Clinic. People taking Alli as directed typically lose three to five pounds more in a year than they would have with just diet and exercise; dieters using Xenical can lose five to seven pounds more than they would have without using fat blockers. The Food and Drug Administration has approved orlistat for long-term use, though the FDA does not have any evidence regarding whether it is safe for people to use fat blockers for more than two years at a time.
Member Comments