Why is Xenical prescribed?
Xenical blocks absorption of dietary fat into the bloodstream, thereby reducing the number of calories you get from a meal. At the usual dosage level, it cuts fat absorption by almost one-third. Combined with a low-calorie diet, it is used to promote weight loss and discourage the return of unwanted pounds.
The drug is prescribed for obese individuals and for overweight people who have other health problems such as high blood pressure, diabetes, or high cholesterol levels. Your weight status is determined by your body mass index (BMI), a comparison of height to weight.
Most important fact about Xenical
Along with dietary fat, Xenical decreases the absorption of some fat-soluble vitamins and beta-carotene. To compensate, it is strongly recommended that you take a multivitamin containing vitamins A, E, D, K, and beta-carotene once a day, at least 2 hours before or 2 hours after taking Xenical.
How should you take Xenical?
Take a capsule of Xenical during, or up to 1 hour after, each main meal. You should follow a nutritionally balanced, low-calorie diet that provides no more than 30 percent of its calories from fat. If you miss a meal, or the meal contains no fat, you can skip the accompanying dose of Xenical.
--If you miss a dose...
Resume taking Xenical at the next meal. Don't try to make up the loss with a double dose. The extra drug won't help.
--Storage instructions...
Store at room temperature, in a tightly sealed container.
What side effects may occur?
Side effects of Xenical are more common during the first year of treatment. If any develop or change in intensity, inform your doctor as soon as possible. Only your doctor can determine if it is safe for you to continue taking Xenical.
• More common side effects may include:
Abdominal discomfort or pain, anxiety, arthritis, back pain, diarrhea, dizziness, earache, fatigue, fatty or oily stools, fecal urgency or incontinence, flu, gas with fecal discharge, gum problems, headache, increased defecation, menstrual problems, muscle pain, nausea, oily discharge, rectal discomfort or pain, respiratory tract infections, skin rash, sleep problems, tooth problems, urinary tract infections, vaginal inflammation, vomiting
Side effects that usually occur after the first year of treatment with Xenical include: depression, leg pain, swollen feet, and tendonitis.
Why should Xenical not be prescribed?
Do not take Xenical if you suffer from "chronic malabsorption syndrome"--a condition that prevents nutrients from passing from your stomach into your bloodstream--or from cholestasis, a blockage in the supply of bile needed for digestion. You'll also need to avoid Xenical if it gives you an allergic reaction.
Special warnings about Xenical
Weight loss begins within 2 weeks and continues for 6 to 12 months. The effect of using Xenical for more than 2 years is still unknown.
Side effects such as diarrhea and abdominal pain may be worse if you continue eating a high fat diet or even take a high-fat meal. Limit your fat intake.
Your doctor will test your thyroid function before starting you on Xenical to make sure that your weight problem is not due to an underactive thyroid gland (hypothyroidism). Xenical is not an appropriate remedy for this problem.
Xenical increases the likelihood of kidney stones. Use it with caution if you have a history of this problem.
If you have diabetes, weight-loss is likely to reduce your blood sugar levels. If you're taking an oral diabetes medication or insulin, your dose may have to be reduced.
Note that the safety and efficacy of Xenical in children younger than 12 years old have not been established.
Possible food and drug interactions when taking Xenical
If Xenical is taken with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important to check with your doctor before combining Xenical with the following:

Cyclosporine (Neoral and Sandimmune)
Warfarin (Coumadin)
Special information if you are pregnant or breastfeeding
The effects of Xenical during pregnancy have not been adequately studied and the drug is not recommended for pregnant women. If you are pregnant or plan to become pregnant, inform your doctor immediately.
It is not known whether Xenical appears in breast milk. Do not take it while breastfeeding.
Recommended dosage
ADULTS AND CHILDREN 12 YEARS AND OLDER
The recommended dose is one 120-milligram capsule 3 times daily with each main meal containing fat.
Overdosage
The results of a massive overdose of Xenical are unknown, although the drug seems relatively harmless. However, any medication taken in excess can have serious consequences. If you suspect an overdose, seek medical attention.