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Weight Loss drugs, supplements, and products have been growing rapidly in recent years with hundreds of different options now readily available throughout the dieting industry. Most of these products are available to purchase online or in health food stores nationwide.

These products generally come with a minimal risk to your health and can have enormous health benefits for the user, and when combined with regular exercise and a healthy, well-balanced diet, it can become extremely easy to obtain and keep your ideal figure.

However, some people still struggle to reach their goals with tried and tested methods and may need to consider prescription medications, this can be for a wide range of reasons.

Orlistat is a prescription medication and this article will provide you with all of the information you need to understand what it is, what it does, the potential side effects, and if it is for you.

What Is Orlistat?

Orlistat is known as a drug designed to specifically combat obesity, also known by the trade name Xenical. Historically, this medication has been sold to patients on the basis of a prescription, however, some countries have now approved the drug for over-the-counter purchase without the need for a prescription.

Orlistat is used to aid weight loss or help to reduce the risk of regaining weight after significant weight loss.

What Does Orlistat Do?

Orlistat helps to reduce the amount of fat absorbed by the body, which in turn, will reduce the daily fat and calorie intake of the patient.

How Does Orlistat Work?

Orlistat acts as a lipase inhibitor: Lipase inhibitors are substances used to reduce the activity of lipases found in the intestine. Lipases are secreted by the pancreas when fat is present. The primary role of lipase inhibitors is to decrease the gastrointestinal absorption of fats.

Orlistat essentially tells your body to absorb less fat.

What Are The Side-Effects Of Orlistat?

Here are some side effects experienced by users, however, you may experience other unknown side effects.

Some potential side effects of taking Orlistat are:

  • oily spotting on underwear
  • flatulence
  • urgent bowel movements
  • fatty or oily stools
  • increased number of bowel movements
  • inability to control bowel movements
  • gas with discharge
  • loose stools
  • stomach pain
  • nausea
  • vomiting
  • diarrhea
  • rectal pain
  • weakness
  • dark urine
  • clay-colored stools
  • itching
  • loss of appetite
  • jaundice (yellowing of the skin or eyes)
  • problems with your teeth or gums
  • cold symptoms (stuffy nose, sneezing, cough, fever, chills, sore throat, flu symptoms)
  • headache
  • back pain
  • skin rash

Do Not Take Orlistat If:

  • People who have a condition where food is not absorbed properly (a malabsorption syndrome).
  • People with cholestasis. This is a condition where bile does not flow properly from the liver to the duodenum.
  • If you are pregnant and/or breast-feeding: Not recommended for use by pregnant or lactating women.
  • If you’re a child under the age of 18: Not intended for use by persons under the age of 18.

Is Orlistat Safe?

Although Orlistat has now been approved in some countries to be purchased over the counter, the medication has caused serious health issues in some patients. One case resulted in a 35-year-old woman suffering from acute liver failure leaving her in need of a liver transplant, this could have been fatal.

There have been other cases related to liver problems, however, a review by the FDA and European Union deemed there to be insufficient evidence that Orlistat is associated with more serious liver disorders than those already listed under common side effects. [1][2]

Has Orlistat Caused Deaths?

There have not been any deaths linked to this medication, however, several cases have seen patients suffering from serious liver problems, one resulted in total liver failure.

Does Orlistat Actually Work?

There have been several clinical trials carried out in order to analyze the efficiency of Orlistat for weight loss. One study carried out in 1998, comprised of over 700 patients who were given 120 mg three times a day for 52 weeks, a placebo group was also used. After 52 weeks, the Orlistat group had lost, on average, 10.3 kgs vs 6.1 kgs in the placebo group. The study also had the participants reduce their calorie intake by 600 calories a day. [3]

The study concluded: “Orlistat taken with an appropriate diet promotes clinically significant weight loss and reduces weight regain in obese patients over a 2-year period”. However, after this time period the effects and benefits are unknown in terms of long term use of Orlistat.


Orlistat is an approved FDA drug designed for the sole purpose of treating obesity and the drug itself works by restricting the amount of fat your body can absorb, This, in turn, would naturally reduce your fat and calorie intake and potentially result in your body also turning to excess fat storage for energy, again resulting in further fat being burned.

It seems it is most effective as part of a calorie restrictive diet, however, more research needs to be carried out in order to confirm this. One study did result in patients losing roughly 10% of their body fat over the course of a 52 week period inline with a daily 600 calorie deficit.

Although this medication has been deemed safe to use under recommended dosage, some case studies do show cause for alarm concerning the user’s health with one particular event resulting in a 35-year-old woman suffering from acute liver failure which could have been fatal without a liver transplant.

This medication does appear to come with significant potential health risks, and you may wish to consider other methods of weight loss, or natural supplements that help the body to burn fat before turning to prescribed medication.

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This article has been reviewed and fact-checked by a certified nutritionist, and only uses information from credible academic sources.