Method What dosage of Quetapine (Seroquel) as an anti-emetic for SN?

[autumnal]

Hi,

I notice Quetapine (Seroquel) is mentioned in the guides as one of the antipsychotics which can be used instead of meto as an anti-emetic for the SN method.

What kind of dosage is typically used for this purpose, and does the dosage required to achieve anti-emetic purposes depend on whether/how much Quetapine someone normally takes as prescribed?

Thanks in advance.

 

[autumnal]

Can anyone help with this?

 

[squirtsoda]

From what I've read, the proper dosage would be what you are already on as prescribed. I wouldn't advise doing this if you aren't prescribed quetiapine or the other acceptable anti psychotics. If you aren't prescribed them, you should use the actual anti emetics listed in Stan's guide or other good resources.

 

[autumnal]

To answer my own question somewhat (and invite evaluation from those more experienced):

Quetiapine - The Drug Classroom
5. Chemistry & Pharmacology

[snipped]

Its pharmacological profile varies by dose. At low doses (~25 mg), it's mainly an H1 antagonist. Moderate doses (50-100+ mg) incorporate greater serotonin receptor antagonism. High doses (300+ mg) recruit D2 antagonism. [my emphasis]

REF: https://thedrugclassroom.com/video/quetiapine/#Chemistry_Pharmacology
​

It's the dopamine receptors that an antiemetic needs to target in order to reduce nausea, so according to the above it would be dosages of Quetiapine at or over 300mg which will have an antiemetic effect.

Questions remaining for me include:

1. Whether the antiemetic effect of Quetiapine at 300mg matches the effectiveness of other dedicated antiemetics (especially Meto)?​
2. When the 300mg+ dose of Quetiapine should be taken in relation to the SN (noting Quetiapine has a stated half-life of seven hours)?​

Thanks in advance for any further help.

 

[autumnal]

Bumping.

 

[Quarky00]

After a short discussion here:

Regarding Quetapine, the dosage required for antiemetic effects seems to be between 300-400mg (or higher). This is a consensus of my findings as well as a post from another user who I believe successfully suicided with SN and used Quetapine as the antiemetic. What is still less clear is whether a single isolated dose at that level is enough, or whether you need to be on that dose for a longer period of time to build up levels beforehand. If you have enough supplies of Quetapine to put yourself on say a week of of 300-400mg per day, it would probably be the most productive option. That is of course assuming there aren't any negative interactions [drug interaction checker link] between Quetapine and your other current medications.

Quetapine works over 15-30 hours and have accumulative effects over days . A single big dose is bad and can make a person go mental . I would not speculate about antipsychotics they are harsh ! Over time tolerance develops , brain adjustes , and it is okay .

Therfore that "300mg required" is unclear , as it's never a single dose -- and we do not know where that 300mg came from . It is stated in many articles but based on what research? . E.g. If one takes 100mg plasma concentration increases over time .

You really have no "findings" , just a number That is no disrespect to you -- I am disappointed at lack of scientific info about that. I share your frustration. It's annoying. They just threw a number ...


Please do not play with antipsychotics, the warning is in the name , i.e PSYCHOSIS .

No disrespect taken, but the page I linked to does seem pretty reputable and conclusive. I would strongly assume that their figures are based on research, probably the initial studies during the development and testing of the drug.

A single large dose of antipsychotics is very unlikely to 'make a person go mental'. What's far more likely is a more pronounced dose of any side effects of Quetapine.

I do share your doubts though over whether a single dose is enough for an antiemetic effect, or whether a more regular course is needed to build up levels of the drug in the body.

Page may be very reputable, but does not detail information about dosage. Otherwise you wouldn't have to ask.. And it's not the only one. Several reliable places state Quetapine dose without reference to research. I guess AE was never a goal there. I share your frustration. Just to alert that people experienced with years of Q on this forum warned of single big dose..

Members explained that Q effects are veryyyy individual. 50mg here , 400mg there , and everything in between. It's wild ;) This may explain why 300mg is not explained, or why it should not be taken literally.