Infectious disease physicians continously warn of the danger of antibiotic overuse. This is often put in terms of increasing resistance, side effects, C.diff and costs. However, these often seem impersonal to the patient who is sick--usually from a viral infection--and is demanding an antibiotic (or even worse is a parent of a sick child). To them, even the threat of a side effect is outweighed by the potential benefit they believe they will gain from an antibiotic.
Powerful evidence has begin to amount, however, that the danger of antibiotic misuse is much greater than the (still true) standard answers. This answer revolves around alterations in the microbiome that are induced by exposure to antibiotics.
To back up, shortly after birth humans are literally covered with bacteria in almost every crevice of their body (skin, digestive tract, mucosal surfaces)--the microbiome or microbiota. These organisms perform vital functions for us that include metabolizing certain substances, preventing "bad" bacteria from gaining hold, and interacting with myriad cells from multiple organ systems (including the nervous system). When this retinue of bacteria is disrupted by antibiotics, certain microbes go "missing" and the result is not good.
All this, as an infectious disease physician, I knew but no where had I seen it presented in a manner that lists the litany of microbiome disruptive diseases and summarizes the leading research in an easy comprehensible manner to provide the full context of the issue. That all changed with the publication of Dr. Martin Blaser's Missing Microbes: How the Overuse of Antibiotics is Fueling Our Modern Plagues which I just finished.
In this book Dr. Blaser, whose work I think will make him a household name in the future, catalogs and expertly explains the importance of the microbiome and theorizes, with ample evidence, that such modern plagues as autism, asthma, reflux, obesity and esophageal cancer may have their origin in the alteration of the microbiome, induced largely by antibiotics (as well as birth via C-section). The point he makes is that anything that prevents an infant from acquiring the microbiome that humans evolved with--whether it be antibiotics or a birth canal-bypassing c-section--will have ramifications.
I once heard a lecture by Dr. Arturo Casadevall in which he described how infectious diseases physicians of the future will spend their time. His answer: microbiome specialists. I am convinced of his and Dr. Blaser's predictions and can't wait to see how unexplained illnesses melt away when viewed in the context of the microbiome and what novel treatments are devised (probiotics, prebiotics, bacteriophages, etc,)
Maybe in the future the possible need for routine fecal transplants is something we can use to scare people out of unnecessary antibiotics?