Confusion
Serotonin plays many important roles in brain function. One of these is that it affects the quality of a person’s memory. Among other things, an alteration in the normal level of this neurotransmitter can result in confusion. [6] It may be hard to place where you are or filter your memories accurately.
Diarrhea
If you have serotonin syndrome, you may experience diarrhea. [7] This is often preceded by stomach upset that may be mild or severe. Diarrhea causes you to stool frequently, sometimes up to or more than three times in one day. Diarrhea caused by serotonin syndrome may be severe, but it is typically bloodless. If you notice blood in your stool when you have diarrhea, you should see a doctor as quickly as possible. It is likely that serotonin syndrome is the cause of this type of diarrhea.