Xenical (Orlistat): What You Need to Know Before You Start

Xenical (orlistat 120 mg) is a prescription medicine that helps with weight loss by blocking some of the fat you eat from being absorbed. If you're considering Xenical, this page gives clear, practical facts: how to take it, what to expect, and when to talk to your doctor. No fluff—just useful info you can use today.

How Xenical works and how to take it

Orlistat works in your gut. It stops enzymes called lipases from breaking down some dietary fat, so that fat passes out of your body instead of being absorbed. Xenical is usually taken three times a day with each main meal that contains fat. If you skip a meal or the meal has no fat, skip that dose.

Take Xenical during the meal or up to an hour after. Most people pair it with a calorie-reduced, lower-fat diet and regular exercise. Expect steady, modest weight loss—often a few percent of body weight over several months—when you combine the drug with lifestyle changes.

Side effects, vitamins, and safety tips

The most common side effects are gastrointestinal: oily or fatty stools, urgent bowel movements, gas with discharge, and increased bowel frequency. These happen because the unabsorbed fat leaves the body. They tend to be worse after high-fat meals; cutting fat in your diet reduces these effects.

Because Xenical reduces absorption of fat-soluble vitamins (A, D, E, K), take a daily multivitamin that contains these nutrients. Take the vitamin at bedtime or at least 2 hours after orlistat so absorption isn't blocked.

Do not use Xenical if you are pregnant or have chronic malabsorption syndrome or cholestasis. There have been rare reports of severe liver injury with orlistat—if you notice jaundice, dark urine, or persistent abdominal pain, stop the drug and call your clinician.

Mention all your meds to your provider. Orlistat can interfere with certain drugs: it may reduce levels of cyclosporine and levothyroxine (separate doses by several hours and monitor blood tests). If you take warfarin, your INR may change—expect closer monitoring and dose adjustments.

Realistic expectations help. Xenical boosts weight loss when you stick to a calorie-controlled, lower-fat plan. It's not a quick fix. If you lose little or have intolerable side effects after a few weeks, talk to your prescriber about stopping or switching options (alli is the lower-dose OTC form of orlistat).

Final practical points: always follow your prescription, keep regular follow-ups for labs and weight, use a daily multivitamin, and avoid very high-fat meals to reduce unpleasant side effects. If you're unsure whether Xenical fits your health needs, a short chat with your doctor will sort that out fast.