MOLEPULE
Iron
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Orlistat is a weight-loss medication that blocks your body from absorbing fat from the food you eat. It is typically prescribed as 120 mg (Xenical) or sold over-the-counter as 60 mg (alli). It should always be combined with a reduced-calorie, low-fat diet and regular exercise. [1, 2, 3, 4, 5]
How It Works
Orlistat acts as a reversible lipase inhibitor. It binds to the enzymes that break down dietary fats in your gut, preventing about \(30\%\) of the fat you consume from being digested. This undigested fat is then passed naturally through your bowel movements, reducing your overall caloric intake. [1, 2, 3, 4]
How to Take It
Common Side Effects
Because unabsorbed fat leaves the body in your stool, digestive side effects are very common and usually peak in the first few weeks of treatment: [1, 2, 3, 4]
Important Warnings
How It Works
Orlistat acts as a reversible lipase inhibitor. It binds to the enzymes that break down dietary fats in your gut, preventing about \(30\%\) of the fat you consume from being digested. This undigested fat is then passed naturally through your bowel movements, reducing your overall caloric intake. [1, 2, 3, 4]
How to Take It
- Dosage: Taken with water during or up to 1 hour after each main meal that contains fat. If you skip a meal or your meal contains no fat, you do not need to take the medication.
Common Side Effects
Because unabsorbed fat leaves the body in your stool, digestive side effects are very common and usually peak in the first few weeks of treatment: [1, 2, 3, 4]
- Oily or fatty stools
- Gas with an oily discharge
- Urgent or increased need to have a bowel movement
- Oily spotting on undergarments
Important Warnings
- Vitamin Absorption: Orlistat can lower your body's absorption of fat-soluble vitamins (A, D, E, K, and beta-carotene). Healthcare providers often recommend taking a daily multivitamin at least 2 hours before or after taking orlistat.
- Drug Interactions: Orlistat can interfere with the absorption of certain medications, including blood thinners (like warfarin) and some HIV drugs.
- Medical Conditions: It should generally be avoided if you have a history of gallbladder issues, kidney stones, or malabsorption syndromes. [1, 2, 3, 4, 5]
