Posted by CamW. on August 29, 2003, at 0:49:17
In reply to new Paxil alternative, posted by lotus on August 28, 2003, at 23:21:10
"The chemical difference between the two products is that the inactive part of the salt (mesylate or hydrochloride) is separated from the active paroxetine molecule in the gastrointestinal tract, ••leaving only the active paroxetine molecule to be absorbed into the bloodstream and provide the intended therapeutic effect••, the company said in a statement."
I haven't read anything that funny since I read somewhere that water has a memory. Most, if not all, solid drugs (eg powders, tablets) are salts. The powder (aka salt) occurs when an acid (HCl - hydrochloric acid) is added to a solution of a basic drug. The acid's H+ reacts with the base's OH- producing water and a salt is precipitated out (consisting of the basic drug bound to a chlorine ion).
This is not quite the whole story, but it shows that any drug salt (ie any drug in solid form) has to dissolve in the intestine; the solid drug has to dissociate into ions in the liquid (chyme) and then are absorbed.
I am not sure if paroxetine HCl is absorbed intact (I sincerely doubt it), but if it did it would probably have an easier time passing through the intestinal was into the bloodstream than the dissociate paroxetine mesylate, as large ionized molecules require active transport mechanisms and will (if at all) diffuse at a much slower rate (osmotically) than a non-ionic molecule.
•• In other words .... duh! I'm giving the writer of the article the benefit of the doubt. I think he added that paragraph as a "non-civil" jab at he company's rhetoric.
Just an observation, and thanks for bringing the article to our attention lotus. Just don't go running out to buy paroxetine mesylate for it's "unique" properties.
Cheers - Cam
poster:CamW.
thread:255207
URL: http://www.dr-bob.org/babble/20030828/msgs/255227.html