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"Will the weight-loss medicine Alli interfere with the effectiveness of my other medication?"

ZocdocAnswersWill the weight-loss medicine Alli interfere with the effectiveness of my other medication?


I'm a 24 year old overweight male. I'm 239 lbs. I just started taking Alli 60mg, 3 times a day. I'm also taking the antidepressant Celexa, and the antipsychotic Abilify. Currently I've been taking the Alli together with my Celexa and Abilify in the morning, but I'm wondering if the Alli will interfere with the absorption of my other medication. Maybe I should be taking them at different times.


Taking multiple medications is a common occurrence, and it is great that you are concerned enough to think about possible interactions. As we age we are more likely to take more and more medications and by the time we are in our 60s and 70s the average number of medications that we take can be as high as seven or eight. With so many medications the likelihood for adverse interactions between drugs increases exponentially. Moreover, doctors are frequently much better at deciding to start a medication than on deciding to stop one and so patients take more and more pills. This is both because of doctors’ inherent bias to prescribe to treat a problem before them and also because the vast majority of scientific studies examine the effect of starting medications with only a handful of studies that examine the effect of stopping medications. To answer your specific question about an interaction between Alli (orlistat), Celexa (citalopram) and Abilifiy (aripiprazole) requires a little bit of research. Though, there are classic medication interactions that are taught in medical school, the explosion in new medicines makes it entirely impossible for physicians to know all the potential interactions of the medications they prescribe with the others patients are taking. Here again, there is a real lack of scientific studies to address this problem. Nevertheless, there are some good resources for both patients and doctors. The most common resources are online databases that doctors can use to import patients’ medications into to check for interactions. There are also patient-friendly databases that are available online by a number of retail pharmacies. Finally, filling all your medications at the same pharmacy or chain allows for the pharmacist to also check for interactions. In your particular case there are no known clinically significant interactions between Alli, Celexa, and Abilifiy. And though there are some medications that you should spread out between your doses of Alli because of interference with absorption, Celexa and Abilify are not ones. You can take them together without fear. You should talk with your primary care physician for more information. Good luck!

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