Xenical vs alli: Which Is Best for You?

xenical vs alli
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If you're trying to lose weight, you might consider a diet pill like Xenical or alli. Both weight loss aids contain the same medication, called orlistat, but in different amounts. Before you make a decision about Xenical vs. alli, learn as much as you can about the pros and cons of each medication. Then, be sure to talk to your doctor before you make a final choice.

What Is Xenical?

Xenical is the prescription dose (120 mg) of orlistat. Xenical is approved by the Food and Drug Administration and intended to be used by individuals with a body mass index (BMI) of 30 or more, or a BMI of 27 or more along with a weight-related condition like type 2 diabetes or hypertension. Xenical can also be used for people who have lost weight and want to prevent weight regain.

Xenical is designed to be used along with a low-fat, low-calorie diet. Those who lose weight with the medication are more likely to be successful over the long-term and keep the weight off for good if they follow a healthy lifestyle. Since this is a prescription medication, you need to get approval from your doctor before you can use it.

This type of medication is called a lipase inhibitor because it causes your body to absorb less fat from the food that you eat. The undigested fat is removed from the body in your stool.

What Is alli?

alli diet pills contain a lower dose of orlistat (60mg). The pills are available over the counter (OTC). That means you don't need a prescription to buy them. But just because the product is available without a prescription, doesn't mean you should take it without first talking to your doctor.

Some people should avoid orlistat, even at the lower dose. For example, women who are pregnant, and people with end-state renal disease (ESRD) or chronic kidney disease (CKD) should not take alli. Consumers who take the heart medication amiodarone should speak to their doctor before taking alli.

alli is easy to find in pharmacies, drug stores, and other locations. The lower dose works the same way the higher dose works, so people who take alli need to follow a low-calorie, low-fat diet and may experience the same side effects as patients taking the higher dose. As with Xenical, people who take alli are also more likely to maintain their weight loss if they stick to a healthy lifestyle.

  • Prescription

  • Higher cost but may be covered by insurance

  • Taken under care of physician

  • Over-the-counter

  • Lower cost

  • Responsible for own use of the medication

Xenical vs alli: Side Effects

For most people, the most noticeable side effect of Xenical or alli is the change in their stool and bowel habits. Because fat is removed through the stool, bowel movements can become loose and oily. If you eat too much fat while taking the medication, the side effects can become more severe and can interfere with typical daily activities.

Because fat content is important, people taking the medication need to be especially careful about dividing their fat and calorie intake evenly throughout the day. No single food that you eat should contain more than 30% of total calories from fat. In addition, since food and nutrient absorption is affected by this medication, the FDA recommends that users take a multivitamin while on either of these drugs.

Xenical vs alli: Cost

A 120-pill pack of alli costs about $60 to $70. You take one pill with each meal, but no more than three pills per day. Coupons for $5 off the less expensive starter pack may be available through the alli website.

If you choose to buy the OTC medication, be sure to purchase from a reliable vendor. In 2014, there were incidences of product tampering and the pills had to be pulled from the market for a short period of time.

A 30-pill prescription of Xenical may cost significantly more, approximately $170 and up. Patients are usually directed to take one pill with each main meal. In some cases, insurance providers may pay for the medication if your weight is the cause of a related illness. But all policies vary, so be sure to check with your insurance carrier to find out if the drug is covered for you.

Xenical vs alli: The Best Choice for You

Orlistat has been shown to be effective at helping some people lose weight and keep it off. But without significant lifestyle modifications, the consequences can be uncomfortable and embarrassing.

In addition, some physicians have expressed concerns about unreasonable expectations. It may be easy to believe that a weight loss pill (either prescription or over the counter) can solve your weight problems.

But even in clinical studies—where patients are given strict care and attention—nearly 40% of patients drop out. The bottom line is that the medication can work for some people if they follow the protocol, including a healthy diet and physical activity, for the long term.

Think about the changes you are willing to make before you talk to your healthcare provider. Then discuss potential side effects and medical considerations with your doctor before making a final decision.

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Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  2. U.S. Food & Drug Administration. Alli orlistat 60mg capsules weight loss aid [label]. Updated May 15, 2017.

  3. Kopelman P, Groot Gde H, Rissanen A, et al. Weight loss, HbA1c reduction, and tolerability of cetilistat in a randomized, placebo-controlled phase 2 trial in obese diabetics: Comparison with orlistat (Xenical). Obesity (Silver Spring). 2010;18(1):108-15. doi:10.1038/oby.2009.155

  4. Williams G. Orlistat over the counter. BMJ. 2007;335(7631):1163-4. doi:10.1136/bmj.39385.347049.80

  5. Torgerson JS, Hauptman J, Boldrin MN, Sjöström L. XENical in the prevention of diabetes in obese subjects (XENDOS) study: A randomized study of orlistat as an adjunct to lifestyle changes for the prevention of type 2 diabetes in obese patients. Diabetes Care. 2004;27(1):155-61. doi:10.2337/diacare.27.1.155

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