Posted by SLS on March 11, 2015, at 6:34:28
In reply to Re: Why isn't there a transdermal patch for Nardil????, posted by cybernut011 on February 25, 2015, at 9:23:01
Emsam inhibits MAO-A at all dosage forms available. However, it is claimed that tyramine ingestion is not dangerous at the dossge of 6 mg/24.
As per company prescribing information:"Pharmacodynamics
MAO exists as two isoenzymes, referred to as MAO-A and MAO-B. Selegiline has a greater affinity for MAO-B, compared to MAO-A. However, at antidepressant doses, selegiline inhibits both isoenzymes. In an in vivo animal model used to test for antidepressant activity (Forced Swim Test), selegiline administered by transdermal system exhibited antidepressant properties only at doses that inhibited both MAO-A and MAO-B activity in the brain. In the CNS, MAO-A and MAO-B play important roles in the catabolism of neurotransmitter amines such as norepinephrine, dopamine, and serotonin, as well as neuromodulators such as phenylethylamine."
"A diet low in tyramine content may be necessary to avoid this interaction. Studies to evaluate the potential for Emsam to inhibit tyramine metabolism have been conducted and, overall, the data for Emsam 6 mg per 24 hours support a recommendation that a modified diet is not required at this dose"
The reason why Emsam requires transdermal administration is because when taken orally, it is metabolized rapidly by the liver into L-amphetamines (L- are relatively inactive) and does not enter the brain appreciably except at the very high dosages necessary to inhibit MAO-A. Nardil needs no such delivery system to inhibit both isoenzymes. There is therefore no reason to produce a Nardil patch.
- ScottSome see things as they are and ask why.
I dream of things that never were and ask why not.- George Bernard Shaw
poster:SLS
thread:917834
URL: http://www.dr-bob.org/babble/20150223/msgs/1077440.html