Q:Given the following passage  "Interactions between alcohol and certain antibiotics may occur and may cause side-effects and decreased effectiveness of antibiotic therapy. While moderate alcohol consumption is unlikely to interfere with many common antibiotics, there are specific types of antibiotics with which alcohol consumption may cause serious side-effects. Therefore, potential risks of side-effects and effectiveness depend on the type of antibiotic administered. Despite the lack of a categorical counterindication, the belief that alcohol and antibiotics should never be mixed is widespread.",  answer the following question. Note that the answer is present within the text.  Question: Why would taking alcohol when on antibiotics be counterproductive?
A:
decreased effectiveness of antibiotic therapy