Call your doctor for medical advice about side effects. Common Xenical side effects are caused by orlistat's fat-blocking action. If you experience any of the following symptoms of an allergic reaction to Xenical: hives, trouble breathing, swelling of your face, lips, tongue, or throat, seek emergency medical attention. If you have: Stop taking Xenical and contact your physician right away. These are signs that the medicine is working properly. As you use Xenical more, these side effects may become less severe and are typically transient: This is not a complete list of side effects and others may occur. Effects of Xenical (more information) Call 1-800-FDA-1088 to report side effects to the FDA. oily or fatty stools; oily spotting in your undergarments; orange or brown colored oil in your stool; gas and oily discharge; loose stools, or an urgent need to go to the bathroom, inability to control bowel movements; an increased number of bowel movements; or stomach pain, nausea, rectal pain. severe stomach pain; severe pain in your lower back; blood in your urine, painful or difficult urination; kidney problems - little or no urinating; swelling in your feet or ankles; feeling tired or short of breath; or liver problems - nausea, upper stomach pain, itching, tired feeling, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).
To find out if Xenical can be taken in addition to any other medications you are currently taking, be sure to discuss all of them with your doctor, including any herbal supplements. If you take cyclosporine, you should take Xenical at least two hours apart from cyclosporine. Levothyroxine and Xenical should be taken at least 4 hours apart if you already take levothyroxine. A more frequent check-in may be required if your cyclosporine levels are being monitored.
If you experience any signs of liver impairment, including appetite loss, itchiness, skin yellowing, dark urine, light-colored stools, or right upper quadrant pain, you should stop taking Xenical right away and get in touch with your doctor. Promptly report any symptoms of back pain or blood in the urine. Report any upper right abdominal pain symptoms right away. Gall stone formation may already be more likely in some Xenical-treated patients. Some Xenical users may experience an increased risk of kidney stones. Nausea and vomiting may occur along with the pain. Rare reports of patients taking Xenical suffering from severe liver damage have been made. Gallstone risk can rise with Xenical-induced weight loss. If you have ever experienced an allergic reaction to Xenical or any of its inactive ingredients, you should avoid using it. Xenical has been shown to decrease the absorption of some vitamins. A multivitamin containing the vitamins D, E, K, and beta-carotene should be taken once daily, ideally at bedtime, at least two hours before or after the administration of Xenical.