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Dr. G. - Another MAOI question
ddnos posted:
Hi Dr. G.

I am curious about something regarding how MAOI'S work, so I've been doing some reading about it.

From my understanding of what I've read, there is an enzyme called monoamine oxidase that's involved in removing neurotransmitters norepinephrine, serotonin, and dopamine from the brain. What MAOI's do is prevents this process from happening, which makes more of those brain chemicals available.

So here are my questions about that:

1. The process where monoamine oxidase removes those neurotransmitters from the brain (someone not taking an MAOI) - is that process something that is constantly happening? I mean, if that enzyme is involved in removing those neurtransmitters from the brain, I assume they get back to the brain and so it's a continuous cycle?

Which leads me to my 2nd question:

2. For those of us on an MAOI where that process is inhibited, i.e. stops the enzyme from removing the neurotransmittters from the brain, how is it that they don't build up in your brain too much? I'm actually referring more specifically to norepinephrine (adrenaline), which is what I've had mega doses of over the past 5-8 years (approx) because of how MAOI's work. In my logical, non-medical mind, it would make sense that over time, adrenaline levels would build up because of how MAOI's stop the process of removing it from my brain. I wouldn't think that it's supposed to mean that those neurotransmitters are then going to build up in my brain, but I sure have gotten a build up of one of them.

If MAOI's stop the enzyme from removing the neurotransmitters from my brain, what happens next? Do they just build up?

Thank you for your time!

Forgiveness is letting go of the hope that the past could have been any different --Unknown
Joseph F Goldberg, MD responded:

Monoamine oxidase doesn't remove neurotransmitters from the brain, it breaks them down and recycles them. If that enzyme is inhibited, the neurotransmitters aren't broken down and recycled, they just do "double shifts" and "triple shifts" of working longer in the synapses between nerve cells. Norepinephrine levels can indeed build up, which is what can cause a hypetensive crisis, and serotonin levels can also build up, leading to the risk for serotonin syndrome.

Dr. G.
ddnos replied to Joseph F Goldberg, MD's response:
Ok, so then if the neurotransmitters aren't broken down and recycled, (when on an MAOI) and you said they just do double and triple shifts, that means they (the neurotransmitters) indeed stay in the brain (non-broken down and recycled)?

WHen not on MAOI and the neurotransmitters are being broken down and that a never ending cycle? I mean, the neurotransmitters in the brain, then the enzyme breaks them down and recycles them, then that cycle just continues?

And, one more thought - since MAOI's work this way, why don't more people who are on them long term run into high adrenaline levels like I have because of that neurotransmitter not being broken down and recycled? I can't possibly be the only person this has happened to. lol

Thank you very much!

Forgiveness is letting go of the hope that the past could have been any different --Unknown
Joseph F Goldberg, MD replied to ddnos's response:
Dear Debbie, Basically, yes, neurotransmitters like just about all body elements get broken down and recycled indefinitely. I can't tell you why some people may be especially sensitive to high adrenaline effects in the absence of other factors which raise adrenaline (eg, other medicines)...just not a common occurrence. Dr G

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Joseph F. Goldberg, MD, is a Clinical Professor of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY. He also maintains a private prac...More

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