Posted by Racer on July 9, 2008, at 10:48:41
In reply to how is this possible?, posted by iforgotmypassword on July 9, 2008, at 8:52:45
> what could be causing that sort of difference?
>
> any experts?I am not an expert, but -- wait, no, I don't even play one on TV...
The laws governing generics say that they have to be bioequivalent to within 10% of the name brand. Usually that means different -- id est: cheaper -- binders and fillers. The 10% figure is mostly a generic-to-generic issue, since that means two generics could conceivably differ by up to 20%. The bigger problem is the binders and fillers can cause odd reactions -- I'm listed in my GP's records as allergic to Prozac, because I had an allergic reaction to one particular generic.
In the case of the extended release versions of medications, my guess is that the release mechanism may be part of the problem with the generics. It might be that the medication isn't being released as reliably, or that something in the binder is interfering with absorption.
For whatever it's worth, the Budeprion is apparently problematic enough that many psychopharmacologists around here simply specify on ALL their prescriptions to fill with name brand Wellbutrin. I know that mine keeps me on a dose that requires the name brand -- 450mg, three 150mg per day.
It's supposed to be equivalent, but that doesn't always work out as well in practice...
Hope that helps..
poster:Racer
thread:838849
URL: http://www.dr-bob.org/babble/20080706/msgs/838990.html