Glutamate antagonists and Opiates (Lamotrigine & Methadone)

[jasoncrest]

I've been prescribed Lamictal (Lamotrigine) recently for depression/bipolar troubles.

From what I can read, it's a Glutamate antagonist, and I read that http://opioids.com/tolerance/glutamate.html
It says that Glutamate can control Addiction and Tolerance to Opiates.

I'm on Methadone too (I take from 60 to 90mg daily).

I wanted to know how Glutamate affects Opiates effects, Glutamate antagonist more specifically, and even more specifically, the action Lamotrigine will have on my Methadone addiction, tolerance, etc...

Does the NMDA-antagonist action of Methadone plays a role/have an interaction with Lamotrigine/Glutamate antagonists.

Advices welcomed.

 

[BilZ0r]

No, Lamotrigine is a Sodium channel modulator just like carbamazepine and phenytoin, it has other effects, but it's bit one is it's effects on sodium channels, trust me.

I don't think it will have any effects, apart from making you feel sleepy.

 

[rashandreflex]

^^
any theories on how a sodium channel modulator affects mood? i take lamictal as well and am curious as to how why it works.

 

[jasoncrest]

No, Lamotrigine is a Sodium channel modulator just like carbamazepine and phenytoin, it has other effects, but it's bit one is it's effects on sodium channels, trust me.
I don't think it will have any effects, apart from making you feel sleepy.

I know it's a sodium channel blocker, but what to do with all the trustable sources saying it's also a Glutamate antagonist?
(www.psychotropics.dk; all the things on pubmed, http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8094961&dopt=Abstract being one of them, www.rxlist.com only says it modulates Glutamate release)
On almost every pharmacology website you can read that Lamotrigine plays a role on Glutamate (and most of them say that it's a Glutamate antagonist)

 

[BilZ0r]

I know it CAN modulation glutamate... but this is one area where I have pharmaceutical industry inside knowledge. Big pharma don't want their antiepileptics to be Na channel blockers, they hide and ignore information that tells them that it is, because they want there new drug to have novel actions.

I've been in clinical trials for Lamotrigine, and I know the people who stereotyped the mechanism of actions of lamotrigine and I'm very close with someone doing research on the biggest new antiepileptic. Trust me, any effects of lamotrigine on glutamate are either insignificant, in the wrong concentration or generated in horrifically designed experiments.

 

[illuminati boy]

Yea, one of their trials was a 3-arm (if memory serves) with Lithium as an arm. It is like pulling teeth to get them to put the Li data side by side with lamotrigine… wonder why…

At any rate with these agents it appears to be all about the voltage sensitive sodium channels and the fact that lamotrigine inhibits some glutamate release probably is not the key piece of the picture.

As a practical, but serious note, if you develop any rashes whatsoever call your Rx physician immediately as it may be a sign of a fairly rare but quite serious syndrome.

I B

 

[jasoncrest]

Thank you guys, you are the best.