Psycho-Babble Medication Thread 87498

Shown: posts 1 to 13 of 13. This is the beginning of the thread.

 

Gabatril and Benzo Difference Mentioned Here

Posted by Cmatt on December 20, 2001, at 5:52:53

Although both have an effect on GABA, there are a
GABA(a) receptor, and a GABA(b) receptor, and although I don't remember off hand which affects which receptor, Gabatril does not affect the same GABA receptor as benzodiazepines, and the GABA(a) receptor does not seem to have the same effect on the body as the GABA(b) receptor.

Cmatt

 

Re: Gabitril and benzos Cmatt

Posted by Elizabeth on December 28, 2001, at 13:39:19

In reply to Gabatril and Benzo Difference Mentioned Here, posted by Cmatt on December 20, 2001, at 5:52:53

Gabitril (tiagabine) doesn't interact with benzo receptors at all. It is a GABA reuptake inhibitor (blocking the GABA transporter to increase the amount of available extracellular GABA, just as SSRIs block the serotonin transporter). Benzos (which are benzodiazepine receptor agonists) work by increasing the effectiveness of GABA at its receptor. Benzos don't directly act at the GABA receptor or increase the amount of GABA.

Another anticonvulsant, Sabril (vigabatrin), works by blocking an enzyme called GABA transaminase which is involved in the metabolism of GABA. This is analogous to the action of MAOIs on monoamines. (Nardil is also a GABA transaminase inhibitor, BTW.)

Ambien is an example of a drug that works selectively at a particular subtype of benzodiazepine receptor; it lacks many of the effects of the benzos (such as their anticonvulsant and muscle relaxant effects).

There are two types of GABA receptors, GABA-A and GABA-B receptors. Baclofen, a medication used for spasticity, is a selective GABA-B agonist and has little effect on anxiety.

-elizabeth

 

Re: Gabitril and benzos Elizabeth

Posted by MB on December 28, 2001, at 14:28:34

In reply to Re: Gabitril and benzos Cmatt, posted by Elizabeth on December 28, 2001, at 13:39:19

> Gabitril (tiagabine) doesn't interact with benzo receptors at all. It is a GABA reuptake inhibitor (blocking the GABA transporter to increase the amount of available extracellular GABA, just as SSRIs block the serotonin transporter). Benzos (which are benzodiazepine receptor agonists) work by increasing the effectiveness of GABA at its receptor. Benzos don't directly act at the GABA receptor or increase the amount of GABA.
>
> Another anticonvulsant, Sabril (vigabatrin), works by blocking an enzyme called GABA transaminase which is involved in the metabolism of GABA. This is analogous to the action of MAOIs on monoamines. (Nardil is also a GABA transaminase inhibitor, BTW.)
>
> Ambien is an example of a drug that works selectively at a particular subtype of benzodiazepine receptor; it lacks many of the effects of the benzos (such as their anticonvulsant and muscle relaxant effects).
>
> There are two types of GABA receptors, GABA-A and GABA-B receptors. Baclofen, a medication used for spasticity, is a selective GABA-B agonist and has little effect on anxiety.
>
> -elizabeth


Elizabeth,
Thanks for the info...very interesting. I guess I just figured that both a) increasing the effectiveness of GABA (benzos) and b) increasing the presence of GABA (tiagabine, vigabatrin) would have similar end results (i.e., I figured increase in GABA activity would *feel* the same no matter what route was taken to get there).

When you mentioned that benzodiazepines bind to the "benzodiazepine receptors" it made me wonder why we have those receptors. Do we know of an endogenous brain-chemical for which these receptors are meant to be recetpive?

So, since the vinyl-GABA and the Gabitril both increase GABA in the brain, does this mean that these drugs affect both types of GABA receptors? I felt no anxiety relief from the Gabitril.

MB

 

Re: Gabitril and benzos MB

Posted by Elizabeth on December 29, 2001, at 6:22:59

In reply to Re: Gabitril and benzos Elizabeth, posted by MB on December 28, 2001, at 14:28:34

> Thanks for the info...very interesting. I guess I just figured that both a) increasing the effectiveness of GABA (benzos) and b) increasing the presence of GABA (tiagabine, vigabatrin) would have similar end results (i.e., I figured increase in GABA activity would *feel* the same no matter what route was taken to get there).

There may be some important differences. For whatever reasons, Gabitril and Sabril aren't used much for anxiety (yet, anyway). I think they may be less effective than benzos.

> When you mentioned that benzodiazepines bind to the "benzodiazepine receptors" it made me wonder why we have those receptors. Do we know of an endogenous brain-chemical for which these receptors are meant to be recetpive?

I don't know. A lot of receptors are named for the first ligand that was found (e.g., the nicotinic subtype of cholinergic receptors), endogenous or not. I think we probably have some sort of endogenous benzos, but I don't know offhand.

> So, since the vinyl-GABA and the Gabitril both increase GABA in the brain, does this mean that these drugs affect both types of GABA receptors? I felt no anxiety relief from the Gabitril.

Yes, just like SSRIs have effects on all types of serotonin receptors (because they just increase the amount of serotonin, which is a nonselective serotonin receptor agonist), Sabril and Gabitril will affect both types of GABA receptors. As you've discovered, though, the road to anxiety relief may be more complicated than just agonizing GABA-A receptors.

-elizabeth

 

Re: Gabitril and benzos Elizabeth

Posted by Lorraine on December 30, 2001, at 23:42:20

In reply to Re: Gabitril and benzos Cmatt, posted by Elizabeth on December 28, 2001, at 13:39:19


So, e, does this mean that if you like that anti-anxiety effects of Nardil, maybe you will like Sabril:-)?

Lorraine

> Another anticonvulsant, Sabril (vigabatrin), works by blocking an enzyme called GABA transaminase which is involved in the metabolism of GABA. This is analogous to the action of MAOIs on monoamines. (Nardil is also a GABA transaminase inhibitor, BTW.)
>
> Ambien is an example of a drug that works selectively at a particular subtype of benzodiazepine receptor; it lacks many of the effects of the benzos (such as their anticonvulsant and muscle relaxant effects).
>
> There are two types of GABA receptors, GABA-A and GABA-B receptors. Baclofen, a medication used for spasticity, is a selective GABA-B agonist and has little effect on anxiety.
>
> -elizabeth

 

Re: Gabitril and benzos Lorraine

Posted by Elizabeth on January 5, 2002, at 4:05:47

In reply to Re: Gabitril and benzos Elizabeth, posted by Lorraine on December 30, 2001, at 23:42:20

> So, e, does this mean that if you like that anti-anxiety effects of Nardil, maybe you will like Sabril:-)?

It's possible, and I'd be interested if anybody has tried it. I haven't heard of Sabril being used in psychiatry, though.

> > Another anticonvulsant, Sabril (vigabatrin), works by blocking an enzyme called GABA transaminase which is involved in the metabolism of GABA. This is analogous to the action of MAOIs on monoamines. (Nardil is also a GABA transaminase inhibitor, BTW.)

 

Re: Gabitril and benzos Elizabeth

Posted by Stephanie S on February 3, 2002, at 12:31:20

In reply to Re: Gabitril and benzos MB, posted by Elizabeth on December 29, 2001, at 6:22:59


> There may be some important differences. For whatever reasons, Gabitril and Sabril aren't used much for anxiety (yet, anyway). I think they may be less effective than benzos.

I've had real decent anxiety relief with Gabatril... I just started it about 5 months ago... I take it in conjunction with my Zoloft... But I don't really have "panic-attack" type anxiety... mine is more jaw-clenching, finger biting, leg jiggling anxiety... :-P

> > So, since the vinyl-GABA and the Gabitril both increase GABA in the brain, does this mean that these drugs affect both types of GABA receptors? I felt no anxiety relief from the Gabitril.
>
> Yes, just like SSRIs have effects on all types of serotonin receptors (because they just increase the amount of serotonin, which is a nonselective serotonin receptor agonist), Sabril and Gabitril will affect both types of GABA receptors. As you've discovered, though, the road to anxiety relief may be more complicated than just agonizing GABA-A receptors.

And maybe just like we all get relief from a variety of SSRI's, the same may be true of the GABA's...

Stephanie

 

Re: Gabitril and benzos Stephanie S

Posted by Elizabeth on February 3, 2002, at 23:45:56

In reply to Re: Gabitril and benzos Elizabeth, posted by Stephanie S on February 3, 2002, at 12:31:20

> I've had real decent anxiety relief with Gabatril... I just started it about 5 months ago... I take it in conjunction with my Zoloft... But I don't really have "panic-attack" type anxiety... mine is more jaw-clenching, finger biting, leg jiggling anxiety... :-P

It's good to hear of a success story! I need to take anticonvulsants anyway, so I'm interested in any additional benefits I might get from them. (Right now I'm on Trileptal, which seems to be preventing seizures but isn't doing much else.)

> And maybe just like we all get relief from a variety of SSRI's, the same may be true of the GABA's...

I'm confused now; what do you mean?

-elizabeth

 

Re: Gabitril and benzos Elizabeth

Posted by Stephanie S on February 4, 2002, at 11:05:30

In reply to Re: Gabitril and benzos Stephanie S, posted by Elizabeth on February 3, 2002, at 23:45:56


> > And maybe just like we all get relief from a variety of SSRI's, the same may be true of the GABA's...
>
> I'm confused now; what do you mean?
>
< smile > What I mean is that just like there are different SSRI's that work better for different people (the one that works for me might not work for my friend), the GABA reuptake inhibitors (as well as other GABA-based meds) might also work better/differently on different people...

I'm not sure I even made it clear now, but hopefully it's at least a little more so. :))

Stephanie

 

Re: Gabitril and benzos Stephanie S

Posted by Elizabeth on February 4, 2002, at 15:24:54

In reply to Re: Gabitril and benzos Elizabeth, posted by Stephanie S on February 4, 2002, at 11:05:30

> < smile > What I mean is that just like there are different SSRI's that work better for different people (the one that works for me might not work for my friend), the GABA reuptake inhibitors (as well as other GABA-based meds) might also work better/differently on different people...

I'm sure that's true (Gabitril was the only GABA reuptake inhibitor that we were discussing, though, wasn't it?).

> I'm not sure I even made it clear now, but hopefully it's at least a little more so. :))

Much more. Your expression "the GABA's" was what had me puzzled; thanks for explaining what you meant by it.

-elizabeth

 

Re: Gabitril and benzos

Posted by Stephanie S on February 4, 2002, at 15:37:00

In reply to Re: Gabitril and benzos Stephanie S, posted by Elizabeth on February 4, 2002, at 15:24:54

> ... the GABA reuptake inhibitors (as well as other GABA-based meds) might also work better/differently on different people...
>
> I'm sure that's true (Gabitril was the only GABA reuptake inhibitor that we were discussing, though, wasn't it?).

Yes... it was the only reuptake inhibitor... but in a couple previous posts there was discussion of some other GABA-based drugs... So I suppose I was actually saying that the mechanism of the reuptake inhibitor as compared to the mechanism of some of the others that were discussed may work better for some and worse for others... :)

Which is why many of us get varying results...

< C/P from earlier post >

"Gabitril (tiagabine) doesn't interact with benzo receptors at all. It is a GABA reuptake inhibitor (blocking the GABA transporter to increase the amount of available extracellular GABA, just as SSRIs block the serotonin transporter). Benzos (which are benzodiazepine receptor agonists) work by increasing the effectiveness of GABA at its receptor. Benzos don't directly act at the GABA receptor or increase the amount of GABA.

Another anticonvulsant, Sabril (vigabatrin), works by blocking an enzyme called GABA transaminase which is involved in the metabolism of GABA. This is analogous to the action of MAOIs on monoamines. (Nardil is also a GABA transaminase inhibitor, BTW.)"

< end c/p >


> Much more. Your expression "the GABA's" was what had me puzzled; thanks for explaining what you meant by it.

Hopefully that will help to clarify my words... I sometimes forget that just 'cause I read through the string all at once and therefore have all of it in my head at once, I'm actually replying to the post just above mine... so you read this thread over a couple months time.... and I was playing "catch up." I must use good web etiquette... I must use good web etiquette... :-P < note to self > :-)

Stephanie

 

Re: Gabitril and benzos

Posted by Elizabeth on February 7, 2002, at 13:34:50

In reply to Re: Gabitril and benzos, posted by Stephanie S on February 4, 2002, at 15:37:00

First of all, a note to Stephanie: yes, you cleared up my confusion. Thanks!

> Yes... it was the only reuptake inhibitor... but in a couple previous posts there was discussion of some other GABA-based drugs... So I suppose I was actually saying that the mechanism of the reuptake inhibitor as compared to the mechanism of some of the others that were discussed may work better for some and worse for others... :)

It's interesting how that works. It's possible that our different problems are due to disruptions in neurotransmission at different stages; that could explain why, for example, some people need a drug that increases the amount of a neurotransmitter in one way while others need one that increases it another way (e.g., Effexor vs. MAOI).

There are really only a few mechanisms by which these drugs work (that we know of, anyway). The ones that I can think of are:

direct agonists, such as bromocriptine, amantadine, and Mirapex (DA); or the opioid agonists like morphine, methadone, oxycodone, etc.

direct antagonists: antipsychotics (DA, and in some cases 5-HT); naltrexone (opioid); Serzone and Remeron also antagonize some 5-HT receptors; TCAs (NE alpha-1); beta-blockers (NE beta)

autoreceptor agonists: clonidine (NE)

autoreceptor antagonists: Remeron (NE)

reuptake inhibitors: Prozac, etc. (5-HT); Effexor (5-HT, NE, and at high doses DA); tricyclics (NE and in some cases 5-HT)

metabolism inhibitors: MAOIs (MAO metaboilizes 5-HT, NE, DA); GABA-t inhibitors like Sabril

release enhancers: amphetamine (DA and I think NE)

[NE = norepinephrine; 5-HT = serotonin; DA = dopamine]

Of the illegal/recreational drugs, cocaine is a 5-HT, NE, and DA reuptake inhibitor; heroin is an opioid agonist; MDMA and fenfluramine are 5-HT release enhancers. (So they're not really all that different from the medicines we use, in any pharmacological sense.) Nobody's entirely sure how LSD works but it has something to do with serotonin. Marijuana (or its main active ingredient, rather) has its own receptor, the cannabinoid receptor. Nicotine is a cholinergic agonist (it specifically activates the cholinergic receptor subtype that took its name: the nicotinic receptor) and also an MAO-B inhibitor. Alcohol is kind of complicated (as a rule, the simpler the molecule, the more complicated the mechanism -- read up on lithium if you don't believe me :-) ).

-elizabeth

 

Re: Gabitril and benzos Elizabeth

Posted by disney4 on November 3, 2002, at 10:07:43

In reply to Re: Gabitril and benzos Stephanie S, posted by Elizabeth on February 3, 2002, at 23:45:56

I am using Neurontin now. I also take a small dose of Klonopin at bedtime. I am considering the switch to Gabatril. What dosage is working for you? From the previous posts, it seems like 4mg is too low and 8 is too high.
Thanks,
Elsie


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