I ' m 37 . I know when I have an infection vs . a virusAge is no qualifier in this , and I bet you don ' t . Most of the time doctors don ' t even know and prescribe antibiotics simply to keep patients happy . Overprescription of antibtiotics and the prophylactic use of antibiotics in the agricultural industry contribute to the widespread bacterial resistance to most discovered antibiotics and the emergence of multidrugresistant strains . And now you ' re telling me that you ' d rather just order fish antibiotics off the internet and take them when you feel you have an infection ? ? As a molecular biologist who researches pathogenic bacteria and the rise of drug resistance I am appalled and depressed that this is what scientific knowledge and advance has come to , people completely shunning it and ordering what they think they need from potentially unsafe sources , and ultimately contributing to the growing global health crisis that is widespread antibiotic resistance . Please don ' t order and take fish antibiotics . The ones I have looked into look dodgy as they aren ' t FDA approved , even for fish . They might contain fillers , pilling agents , or other impurities that aren ' t allowed in human medications . Also , because they aren ' t FDA approved there ' s no guarantee that the pills contain the antibiotic they are labelled with , either in amount or purity . Maybe they say 250 mg but are actually only 100 mg of active ingredient . Giving yourself a low dose of amoxicillin is an easy way to increase bacterial resistance in fact , it ' s what I regularly do in the lab to create drug resistant mutant bacteria that I can then look at their gene expression of . It takes less than 10 generations of exposure to lessthanlethal doses of antibiotics for bacteria to establish resistance . Some pathogenic bacteria have generation times of less than an hour . I am probably waffling but PLEASE don ' t order antibiotics online ! It ' s not a good idea .