Serotonin syndrome is a toxic state caused mainly by excess serotonin within the central nervous system. It results in a variety of mental, autonomic and neuromuscular changes, which can range in severity from mild to life-threatening. Most cases are self-limiting.
Excessive accumulation of serotonin in the body creates the symptoms of serotonin syndrome. Typically, nerve cells in the brain and spinal cord produce serotonin that helps regulate attention, behavior and body temperature.
DEFINITION Serotonin syndrome (ie, serotonin toxicity) is a potentially life-threatening condition associated with increased serotonergic activity in the central nervous system. It is seen with therapeutic medication use, inadvertent interactions between drugs, and intentional self-poisoning [1].
Serotonin syndrome occurs when someone has an excess of the neurotransmitter serotonin in their nervous system. The condition's symptoms generally fall into three categories: Altered mental status (irritability, agitation, restlessness, and anxiety)
Research suggests schizophrenia may be caused by a change in the level of 2 neurotransmitters: dopamine and serotonin. Some studies indicate an imbalance between the 2 may be the basis of the problem. Others have found a change in the body's sensitivity to the neurotransmitters is part of the cause of schizophrenia.
Too much serotonin, however, could result in serotonin syndrome, which could lead to symptoms of restlessness, hallucinations, and confusion. Serotonin is also known as a hormone within the enteric nervous system of the body, primarily found within the gastrointestinal tract (gut).
It has long been suggested that over-activity of the serotonin system may relate to mood disorders such as depression and anxiety, as these seem characterized by too much withdrawal and avoidance.
Serotonin syndrome happens when you have too much serotonin (a normal chemical) in your body. It's usually caused by taking drugs or medications that affect serotonin levels. Stopping the drug(s) or medication(s) causing serotonin syndrome is the main treatment.
Researchers also found that the incidence of serotonin syndrome was 0 to 4 cases per 10,000 person-years of exposure to coprescription of triptans and SSRI or SNRI antidepressants.
Core Tip: Chronic serotonin syndrome (SS) is an evolving concept. It may present with nonspecific symptoms such as generalized body pain, stiffness/rigidity, insomnia, restlessness, and tiredness.
Researchers believe that abnormal functioning of brain circuits that involve serotonin as a chemical messenger contribute to mood disorders (depression and bipolar disorder).
The main areas of serotonin research provide no consistent evidence of there being an association between serotonin and depression, and no support for the hypothesis that depression is caused by lowered serotonin activity or concentrations.
According to the study, over time, people who took antidepressants long term were more outgoing and emotionally stable at the end of the process. To put it in terms of the study, they showed less neuroticism and more extroversion, which are both factors affected by the serotonin in the brain.
Guilt, therefore, was uniquely affected by the interaction between trait empathy and the serotonin-depleted state. Serotonin induced a distinct emotional profile in highly empathic individuals.
Serotonin has also been implicated in the causation of hallucinations, based on the fact that a number of hallucinogenic drugs, like lysergic acid diethylamide (LSD), mescaline, psilocybin and ecstasy, appear to act, at least in part, as serotonin 5 HT2A receptor agonist or partial agonists.
The authors hypothesize that schizophrenia is characterized by abnormally low prefrontal dopamine activity (causing deficit symptoms) leading to excessive dopamine activity in mesolimbic dopamine neurons (causing positive symptoms).
A key hormone of the HPA axis is cortisol, and hypercortisolemia may precipitate or exacerbate psychotic symptoms. The thyroid hormones have been studied for many decades, but in more recent times, the relationship of hyperthyroidism to the onset of schizophrenia has increased evidence.
Selective loss of Purkinje cells has previously been described in neuroleptic malignant syndrome and heatstroke, conditions that are characterized by hyperthermia. This suggests that hyperthermia may be a causative factor of brain damage in serotonin syndrome.
Most cases of serotonin syndrome start within 24 hours after starting or increasing a serotonergic medication and the majority of those start within six hours.
The serotonin levels were measured by ELISA every hour at night (20:00-08:00 h) and every 4 h during the daytime (08:00-20:00 h). Ours results show that the maximum levels of serotonin in plasma were obtained at 09:00 and 22:00 and a minor peak at 01:00 h.
Serotonin has been linked to fatigue because of its well known effects on sleep, lethargy and drowsiness and loss of motivation.