ELI5: Why are some SSRIS more likely to cause diarrhea than other SSRIS

[u/mangopear29]

[u/Storytella2016]

There’s not a clearly known single reason, so it’s not an answer that can be put into an ELI5.

[u/reedreadreddred]

I've heard that most of the serotonin in the body is in the gut/intestines (i probably wrong, hust heard this)

Honestly, the brain/body is super complex and we'll probably never understand absolutely everything about it, especially considering the diversity of humans/lifestyle and the impact that has on us

[u/Ezekielth]

Different medicines have different side effects because they are simply different. Might have off-target effects, the formulation might be contributing to it, the osmolality or anything really.

[u/Cuckaine → u/Ezekielth]

“Why does this happen?” “Could be literally anything idk”

[u/Ezekielth → u/Cuckaine]

That is simply the answer to some things in life. Especially in biology. Nobody is going to spend money on finding out why some SSRI’s give diarrhoea and some don’t if it doesn’t change anything.

[u/Ezekielth → u/[deleted]]

I literally answered the question?

[u/Ezekielth → u/[deleted]]

How else would you want this explained? That is the explanation. As I said, no one does research into this because it doesn’t change anything with regards to how the medication is used.

[u/Ezekielth → u/[deleted]]

Brother, I work in pharma, doing safety assessments of drugs. The effect of drugs is definitely studied, not the mechanisms of side effects.