Psycho-Babble Medication | about biological treatments | Framed
This thread | Show all | Post follow-up | Start new thread | List of forums | Search | FAQ

ritanserin, pimavanserin, and lumateperone undopaminergic

Posted by SLS on September 12, 2021, at 12:52:04

In reply to Re: Best serotonin 5-HT2C antagonist? SLS, posted by undopaminergic on September 12, 2021, at 8:30:01

Hi, UD.


> Hi.
>
> > Ritanserin is probably the most selective 5-HT2 antagonist in the world. When I looked in on it a bunch of years ago, it was reported to be virtually devoid of side effects. It is a drug without an indication. It has no other purpose that I recall other than being an antidepressant augmenter. By itself, it is inert.
> >
> >
> > - Scott


> But ritanserin is not clinically available as far as I know.
>
> -undopaminergic

Exactly.

Ritanserin is a great drug without an indication. What clinical value does this drug have as monotherapy? None. However it's possible that ritanserin would be a miracle augmenter of antidepressant treatment.

Ritanserin acts as a "selective" ligand of:

1. 5-HT2a receptors (Ki = 0.45 nM)
2. 5-HT2c receptors (Ki = 0.71 nM).

Ritanserin is labeled either a "selective" or "non-selective", depending on the authors of the available medical literature. At these receptors, ritanserin functions as an INVERSE AGONIST. An inverse agonist really acts as a super-antagonist. If a receptor is antagonized (blocked), it prevents the neuron from being stimulated in a neutral fashion. For example, let's say that the baseline level of neuron excitability in the absence of pharmacological intervention neuronal = 100 units. A pure antagonist might bring the excitability of the the neuron down = 0 units. Now, an "inverse agonist", when bound to the same receptor, will move the level of excitability to *below* the baseline = negative (-) 100. The inverse agonist actually suppresses the excitability of a neuron *below* its baseline. In a way, an inverse agonist actually causes a cell to do exactly the *opposite* of what an agonist does.

Although sometimes considered to be non-selective for all of the three subtypes of 5-HT2 receptors, Ritanserin really isn't. It does not bind to the 5-HT2b receptor subtype.

There are three drugs other drugs that are supposed to be potent 5-HTa/c antagonists:

1. Pimavanserin
2. Roluperidone
3. Lumateperone.

Unlike ritanserin, these drugs have other pharmacological properties. They aren't "clean". Of these, both pimavanserin and lumateperone have been approved by the FDA for the treatment of hallucinations and delusions associated with Parkinson's disease. In addition, they seems to be effective in treating schizophrenia to treat both positive AND negative symptoms. These drugs are currently under investigation for treating Bipolar Depression.


- Scott


Some see things as they are and ask why.
I dream of things that never were and ask why not.

The only thing necessary for the triumph of evil is that good men do nothing.

 

Thread

 

Post a new follow-up

Your message only Include above post


Notify the administrators

They will then review this post with the posting guidelines in mind.

To contact them about something other than this post, please use this form instead.

 

Start a new thread

 
Google
dr-bob.org www
Search options and examples
[amazon] for
in

This thread | Show all | Post follow-up | Start new thread | FAQ
Psycho-Babble Medication | Framed

poster:SLS thread:1116890
URL: http://www.dr-bob.org/babble/20210723/msgs/1116921.html