Posted by yxibow on May 27, 2006, at 0:43:13
In reply to Re: Are Family Doctors prescribing EMSAM?, posted by jealibeanz on May 26, 2006, at 1:42:58
> I know that the cytochromes are part of the electron transport chain involved in the degradation of medications in the liver. Is this necessary when breaking down all medications, or just those that go through the GI tract? Does transdermal delivery avoid processing in the liver?
No, transdermal delivery does not avoid the processing of what, as was correctly noted, an older drug used in Parkinson's (Eldepryl, selegiline hydrochloride) often in combination with Sinemet (levodopa/carbidopa).
It is simply a different method of entry into your bloodstream. A number of medications and chemical substances can enter your bloodstream through your skin -- it is porous.
If you cover too much of your body with Benadryl or Ben-Gay creams you may reach a toxic level inside your system, as the medication goes through the layers of your skin, the outer always being dead, which protects us from some substances being harmful, but not all.
Once the drug is in your bloodstream, it will eventually be metabolized by your liver (or in the case of certain, fewer medications, that bypass the liver route and go through your kidneys, such as Serax -- often through a process known as glucuronidation.)
And as for psychiatrists knowing P450 -- if they dont, they're in serious jeapordy of their license.Its a basic principle -- but I agree, if you are "old school" you may not have been taught all the intricacies which are now routinely taught in medical school, and which if you read a drug monograph or as we call it in the US, a PI, or prescribing information, they will list testing for cytochromes.
This wasn't done routinely until the last decade because the knowledge wasn't out there -- as one who takes polypharmacy (multiple medications), I've had a few curveballs with mixing modern medications with older ones and having to adjust to avoid things like serotonin syndrome.
poster:yxibow
thread:647686
URL: http://www.dr-bob.org/babble/20060525/msgs/649205.html