Serotonin: 9 Questions and Answers
8. Since both dementia and Alzheimer's disease are brain-related conditions, does serotonin play a role in either problem?
In much the same way that we lose bone mass as we age, some researchers believe that the activity of neurotransmitters also slows down as part of the aging process. In one international study published in 2006, doctors from several research centers around the world noted a serotonin deficiency in brains of deceased Alzheimer's patients. They hypothesized that the deficiency was because of a reduction in receptor sites -- cells capable of receiving transmissions of serotonin -- and that this in turn may be responsible for at least some of the memory-related symptoms of Alzheimer's disease. There is no evidence to show that increasing levels of serotonin will prevent Alzheimer's disease or delay the onset or progression of dementia. However, as research into this area continues, this could also change.
9. What is serotonin syndrome -- and is it common or dangerous?
SSRI antidepressants are generally considered safe. However, a rare side effect of SSRIs called serotonin syndrome can occur when levels of this neurochemical in the brain rise too high. It happens most often when two or more drugs that affect serotonin levels are used simultaneously. For example, if you are taking a category of migraine medicines called triptans, at the same time you are taking an SSRI drug for depression, the end result can be a serotonin overload. The same can occur when you take SSRI supplements, such as St. John's wort.
Problems are most likely to occur when you first start a medication or increase the dosage. Problems can also occur if you combine the older depression medications (known as MAOIs) with SSRIs.
Finally, recreational drugs such as ecstasy or LSD have also been linked to serotonin syndrome.
Symptoms can occur within minutes to hours and generally include restlessness, hallucinations, rapid heartbeat, increased body temperature and sweating, loss of coordination, muscle spasms, nausea, vomiting, diarrhea, and rapid changes in blood pressure .
Although not a common occurrence, it can be dangerous and is considered a medical emergency. Treatment consists of drug withdrawal, IV fluids, muscle relaxers, and drugs to block serotonin production.