Posted by Shawn. T. on October 9, 2003, at 23:20:49
In reply to Re: BIG differences between benzos? » Shawn. T., posted by Viridis on October 9, 2003, at 0:57:29
Alprazolam is considered to be a nonselective benzodiazepine agonist (see http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12420154&dopt=Abstract ). I mentioned in the previous post that I believe that clonazepam is also nonselective. The binding affinities for these drugs at the various alpha subunits probably differ, but I don't have access to any data on the subject. My point is that cross tolerance probably does develop between the two drugs. In a mouse model of chronic benzodiazepine exposure, both drugs induced a similar pattern of tolerance (see http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=1652596&dopt=Abstract ). In addition, evidence seems to suggest that alprazolam develops cross tolerance with other benzodiazepines in all but a few cases (see http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2889723&dopt=Abstract ).
I don't think that it's reasonable to judge the possibility of the development of cross tolerance between two drugs based upon the chemical structure of the drugs. On the other hand, I would expect benzodiazepines to differ in the levels of tolerance that they induce to various effects; this would depend on how they interact with the different GABA-A receptor subunits. Based on our current understanding of the pharmacology of alprazolam and clonazepam, I think that finding a pharmacological explanation for the phenomenon that you've experienced would be very difficult.
Shawn
poster:Shawn. T.
thread:266360
URL: http://www.dr-bob.org/babble/20031004/msgs/267605.html