orlistat, Xenical, alli (cont.)

Pharmacy Author:
Medical and Pharmacy Editor:

Some dietary vitamins bind to fat (vitamins A, D, E and beta- carotene). When orlistat is taken, these vitamins are not absorbed and are eliminated in the stool in increased amounts along with the fat. Therefore, patients taking orlistat should take a multivitamin containing these "fat-soluble" vitamins to ensure that adequate amounts of the vitamins are available for absorption. To ensure that the vitamins in the multivitamins are not bound to fat like the vitamins in the diet, the multivitamin should be taken at least two hours before or several hours after the orlistat.

DRUG INTERACTIONS: The blood thinning effect of warfarin (Coumadin) depends on the amount of vitamin K in the body, and vitamin K is one of the vitamins that binds to fat. Patients receiving warfarin who begin orlistat should have their blood clotting monitored closely because the orlistat may cause levels of vitamin K to decline. This will increase the effects of warfarin and lead to abnormal bleeding from the warfarin. There is no evidence that a deficiency of vitamin K occurs in patients who are taking orlistat.

Orlistat may reduce the absorption and blood levels of cyclosporine (Sandimmune) when both drugs are administered together. Therefore, cyclosporine should be administered two hours before or after orlistat, and more frequent monitoring of cyclosporine levels may be needed.

Hypothyroidism has been reported when orlistat and levothyroxine (Synthroid, Levoxyl, Levothroid, Unithroid) were combined. Patients treated with both orlistat and levothyroxine should be monitored for changes in thyroid function. The orlistat and levothyroxine should be taken at least four hours apart.

PREGNANCY: Safe use of orlistat during pregnancy has not been established. Therefore, orlistat is not recommended during pregnancy.

NURSING MOTHERS: It is not known if orlistat is secreted in breast milk. Therefore, it probably should not be taken by nursing mothers.

Medically reviewed by Eni Williams, PharmD

Reference: FDA Prescribing Information


Medically Reviewed by a Doctor on 2/17/2015


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