As does Histamine.
But I'd like to be on the lookout so I can be my best self.
I take antihistamines from April to September. Loratadin absolutely has a negative effect on my mood. Mostly because I feel tired I believe. Switched to Ebastin and no more tiredness. However, I am starting to suspect that it also does affect my mood in some way or another.
During winter I take a pill as a precautionary if I’m going to be in any dusty spaces. The day after I sometimes experience mood swings that I cannot explain.
Aged food & drink is higher in histamine. Red wine more than white wine. Dark spirits more than clear spirits. Red meat more than white meat. It can cause spontaneous erections, 60mg of histamine can be used for erectile dysfunction. Histamine can increase blood saturation levels and help reduce the symptoms of COPD and other respiratory problems.
If you consumed alot of histadine, like several heaped table spoons with meals throughout the day, depending on your age and health you will notice some or all of the above. Its one of the fastest amino acids into muscle, its untouched by the liver.
I dont know why you are taking anti-histamines, histamine helps the white immune cells move through tissue, it causes inflammation, there is also a histamine feedback loop in the brain which affects sleep patterns, which is why anti-histamines can help people get to sleep, but lots of histamine can improve sleep conversely.
Loads of studies exist that can be found on Google Scholar, but multiple chemicals affect peoples personality, and their health.
If you want to read up on this, also look at the pathways and other chemicals which work with histidine (or any other amino acid) for that matter.
Did you control for other variables?
In European woman, the most common bacteria in a woman's vagina's is Lactobacillus largely due to the milk product consumption in their die.
However whilst Western medicine considers Lactobacillus to be a probiotic, other cultures who do not consume milk products in as large a quantity have different bacterial profiles in their vagina's.
Japanese people claim to be able to smell gone off milk oozing from the pores of westerners.
The presence of a particular strain of bacteria (whose name I dont have to hand right now) in a woman's vagina will also predict whether they have freckles or not.
Biology is a fascinating subject and very much open to debate.
Humans are very good at detecting rancid milk from the smell; I believe nobody's developed a machine better than us yet.
Japanese people claim to be able to smell gone off milk
oozing from the pores of westerners.
I think I remember hearing that there were some specific derogatory terms for Westerners based on this smell, but I could be wrong.
Reciprocly, the weight gain induced by certain SSRI is tought to be caused by an antihistaminic effect³.
It would not be surprising if other antihistamines (at least those that cross the BBB) had similar effects because antihistamines are frequently promiscuous (i.e. they have significant affinities with a lots of targets other than the one that make a drug effective) but I would be surprised if histamine, or its inhibition, was directly (with the exclusion of the miserable feeling that comes with allergies) implicated in moods changes.
1- https://en.wikipedia.org/wiki/Brompheniramine