Interactions

Which substances may interact with Xenical?

Before starting treatment, make sure your doctor knows if you are taking other medicines (including those not prescribed by your doctor). This is important as using more than one medicine at the same time can strengthen or weaken the effects of the medicines. Xenical does not affect most commonly prescribed medicines. However, it increases the effect of some lipid lowering medicines and therefore your doctor may change your dose of this medicine. Xenical reduces the absorption of supplements of some fat-soluble nutrients, particularly beta-carotene and vitamin D, E. You should therefore follow your doctor's advice in taking a well balanced diet rich in fruit and vegetables. If a multivitamin supplement is recommended, it should be taken at least two hours after the administration of Xenical or at bedtime.

During pharmacokinetic studies no interactions with alcohol, digoxin, nifedipine, oral contraceptives, phenytoin, pravastatin or warfarin have been observed.

A reduction in cyclosporin plasma levels has been observed when Xenical is co-administered. Therefore it is recommended to monitor more frequently than usual the cyclosporin plasma levels when Xenical is co-administered.

Do not take Xenical (orlistat) without first talking to your doctor if you are taking warfarin (Coumadin).

You may not be able to take orlistat, or you may require a dosage adjustment or special monitoring during your treatment if you are taking any of the medicines listed above.