The push towards usage of generic drugs has been strong in the last few years.  On one side you have frugal people who resist the pushy advertising and marketing advances of pharmaceutical companies.  On the other side, you have health insurance companies who are desperate to cut costs wherever possible, several of which have begun to demand that their customers choose generics whenever they are available.

Unfortunately, new data suggests that generic drugs, while they contain the exact same medicine as their "name brand" counterparts, may not work as well.  The problem lies with the inert ingredients, that other stuff that makes a pill a pill.  This binder is often made of a cheaper chemical in generic drugs (it's not just marketing that keeps prices high) and it may not dissolve or disperse into the patient's blood stream as well as the name brand version.

I had always wondered about this myself, because this is a known issue with vitamins.  Most reliable sources (i.e. sources which are not actually trying to sell you their line of vitamins) agree that generic and off brand vitamins don't dissolve as well.  This leads to a poorer up-take of the vitamins into your system, and consequently a waste of a certain percentage of the nutrients.  The rule of thumb I have heard is that you waste more with a generic vitamin by not absorbing it than you save by buying a slightly cheaper brand.

It's one thing when you're talking about a vitamin supplement, which for most people is not a critical care issue.  It's entirely a different thing when you are talking about an anticonvulsant drug for the treatment of epilepsy.  Or insulin for a diabetic.

One syndicated newspaper columnist ran independent laboratory tests on the antidepressants Wellbutrin XL versus its generic counterpart Budeprion XL.  The lab found that both medicines released the same amount of dosage over a 24 hour period, but that the generic version released the drug at a different rate than the name brand Wellbutrin.

Confusingly, patients are reporting more (and more serious) side effects on generic drugs compared to the name brand version.  There is nothing (that we know of) about the dissolution rate of drugs which would change the severity or incidence of side effects.  Which means that either the generics really aren't using the exact same chemicals (unlikely, but possible), or that there is a reverse placebo effect happening.  After all, a patient knows when she is taking Wellbutrin or its generic form.

Further confusing the issue is my personal skepticism regarding any data on this matter.  The report from the newspaper columnist (quoted in the New York Times article) sounds legit.  But there is a lot of money on the line here for the pharmaceutical companies.  Generic medications have taken a big bite out of their profits, and I can't help but wonder how far they would go in order to dig up (or fabricate) evidence that generics are not actually as good as the latest shiny new (heavily advertised) medication.