Has Promethazine The Same Effect As Cypro?

aguilaroja

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Has Promethazine the same effect as Cypro?
(No), I am not aware of promethazine having serotonin-lowering effects that cyproheptadine is known for.
they are earlier generation anti-histamines.
There are reports about promethazine having some parallel effects ondasetron. Ondasetron is another medication class that may lower serotonin. So far though, I know no strong evidence about promethazine acting as a serotonin antagonist. Promethazine action reducing vertigo or nausea may be through a different action. Perhaps other readers know more.
Ondansetron or promethazine: Which one is better for the treatment of acute peripheral vertigo? - PubMed - NCBI
 

Kingpinguin

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(No), I am not aware of promethazine having serotonin-lowering effects that cyproheptadine is known for.
they are earlier generation anti-histamines.
There are reports about promethazine having some parallel effects ondasetron. Ondasetron is another medication class that may lower serotonin. So far though, I know no strong evidence about promethazine acting as a serotonin antagonist. Promethazine action reducing vertigo or nausea may be through a different action. Perhaps other readers know more.
Ondansetron or promethazine: Which one is better for the treatment of acute peripheral vertigo? - PubMed - NCBI

Has Promethazine the same effect as Cypro?

Promethazine, a competitive inhibitor of 5-HT2 receptors,12

At the Bedside: Serotonin syndrome: a brief review


In my opinion many of the antihistamines have anti serotonin properties. Even loratadine and desloratadine. The molecule structure are very similair to cyphro. Ive used a lot of cyphro and tried different anti histamines and i feel many of them inhibit serotonin as they tend to give me slight constipation and hunger. Many antihistamines tend to inhibit dopamine aswell tho. Its an under studied area. And I even think theres other anti histamine options which block serotonin equally as good as cyphro but doesnt have the same dopamine D3 inhibiting effect as cyphro has.
 

aguilaroja

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Joined
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Messages
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Promethazine, a competitive inhibitor of 5-HT2 receptors,12
At the Bedside: Serotonin syndrome: a brief review

In my opinion many of the antihistamines have anti serotonin properties. Even loratadine and desloratadine. The molecule structure are very similair to cyphro. Ive used a lot of cyphro and tried different anti histamines and i feel many of them inhibit serotonin as they tend to give me slight constipation and hunger. Many antihistamines tend to inhibit dopamine aswell tho. Its an under studied area. And I even think theres other anti histamine options which block serotonin equally as good as cyphro but doesnt have the same dopamine D3 inhibiting effect as cyphro has.

Thank you for the reference. Since serotonin is regarded as a happiness chemical for commercial reasons, little researcher into anti-serotonin, via anti-histamines or elsewhere, is expected soon.

On further review, wikipedia does list Promethazine as an antihistamine with
Serotonin receptor antagonist - Wikipedia

I do not have ready access to the 1987 Sanders-Bush chapter in the Meltzer book that the article cites, which may cite earlier references. Most of the references about antiserotonergic actions of promethazine go back 40 years, including journals without electronic access that far back.

Investigations on unspecific, intestinal elimination in the case of poisoning with psychotropic drugs. - PubMed - NCBI
The effect of the antihistaminic drugs on the central action of 5-hydroxytryptophan in mice. - PubMed - NCBI
A comparison of the effects of chlorpromazine and more selective histamine and 5-hydroxytryptamine antagonists on human IgG synthesis in vitro. - PubMed - NCBI

I agree the dopamine antagonism action of cyproheptadine is concerning and may be non-restorative. In early years of studying Dr. Peat's work and before, I individually experimented with many anti-histamines, of each generation and each class, including their ability to counteract tryptophan intake effects. The later generation antihistamines are largely intended to have less brain effect and thereby less drowsiness. So by design, their would be less serotonin antagonism in the CNS.
H1 antagonist - Wikipedia

For better metabolism, there may be rationale for keeping brain serotonin lower:
Tryptophan, serotonin, and aging
"Stress also liberates free fatty acids from storage, and these fatty acids increase the uptake of tryptophan into the brain, increasing the formation of serotonin. Since serotonin increases ACTH and cortisol secretion, the catabolic state tends to be self-perpetuating. This process is probably a factor influencing the rate of aging, and contributing to the physiological peculiarities of aging and depression.
Malnutrition, and specifically protein deficiency, produces an inflammatory state that involves extreme serotonin dominance. Stress or malnutrition prenatally or in infancy leads to extreme serotonin dominance in adulthood. Other functions of tryptophan are reduced, as more of it is turned into serotonin.
Decreasing tryptophan or decreasing serotonin improves learning and alertness, while increased serotonin impairs learning."
 

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