litvishechosid: every medicine you take is made up of two things: the drug itself (called the “active ingredient”) and some starch, for a solid pill, or liquid (inactive ingredients), to make up the bulk of the medicine, since the amount of the drug itself is too small to make a pill out of. A generic drug has the same active ingredient as the brand name, but the inactive (filler) ingredients will differ.
There’s an effect in medical issues called “placebo,” That means that just taking the medicine makes someone feel better even if the medicine has no “real” effect. Nobody has ever been able to figure out exactly how it works, but it’s real and it can really mess up your drug research. So there’s a technique in experimentation called a “double blind” trial.
You take your group of people for testing, and divide them randomly into two groups. One group you give the real medicine to, and the other you give a fake sugar pill that looks exactly like the real one (one of the “blinds” in “double-blind”). Then you have them evaluated by doctors who don’t know which patient is getting which (the second “blind” in the “double-blind.”) This way you’re sure that the doctors aren’t subconsciously changing their evaluation to go with their previous knowledge and the patients aren’t having a placebo effect and confusing both themselves and the doctors.
All drugs which go on the market have to pass this kind of test – brand-name or generic. For generic they test the drug ingredient against both the brand-name and a sugar pill, to make sure it acts the same. So there is no difference in the drug itself, just in the fillers the companies use to make up the pill.