Serotonin Syndrome Symptoms

Serotonin syndrome refers to a serious drug reaction, where an abnormally high level of serotonin accumulates in the body. Serotonin is the neurotransmitter, concerned with regulating some crucial brain functions, and it is produced by nerve cells of the brain, spinal cord and intestine. Serotonin regulates appetite, sleep, alertness, memory and body temperature. Serotonin syndrome usually occurs, due to overdose of serotonergic drugs, or drugs that raise the level of serotonin in the body. Most often, it results, when more than one drug, that can increase the level of serotonin are taken together. The condition can increase the serotonergic activity of the central nervous system, which in turn, can manifest in several cognitive and other problems. The reverse condition of serotonin syndrome is serotonin deficiency, which is characterized by its low levels in the body.

Causes of Serotonin Syndrome

As has been mentioned already, it is caused by an abnormally high serotonin level in the body, due to drug reaction. Drug overdose, as well as recreational use of drugs can lead to this condition. The medications that more commonly cause an increase in the level of serotonin in the body are antidepressants, such as serotonin reuptake inhibitors (SSRIs), monoamine oxidase inhibitors (MAOIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), bupropion, tricyclic antidepressants (TCAs) and nefazodone. Apart from these depression medications, central nervous stimulants, anti-migraine medications like, naratriptan, almotriptan, sumatriptan, pain medications like, tramadol, fentanyl, meperidine, certain anti-nausea medications, illicit drugs such as cocaine and amphetamines, lithium and ritonavir can also cause this condition, if taken excessively.

Serotonin Syndrome Signs

Low serotonin syndrome symptoms are usually mild. But a significant increase in the level of serotonin can present severe symptoms, and can lead to shock at times, which is a life-threatening complication.

• Restlessness
• Increased heart rate
• Shivering
• Excessive sweating
• Headache
• Dilated pupils
• Twitching of muscles or myoclonus
• Diarrhea and vomiting

A severe case of serotonin syndrome, on the other hand can produce the following symptoms:

• Irregular heartbeat
• High blood Pressure
• High fever
• Confusion
• Poor coordination
• Hallucinations
• Seizures
• Loss of consciousness or coma

Treatment for Serotonin Syndrome

There are no specific tests or laboratory examinations to detect it. Diagnosis of the condition is based on the detailed study of the patient's medical history, the symptoms and the medications he or she has been using. In addition to these, physicians can carry out certain tests like, blood culture, complete blood count test, tests to measure the level of thyroid hormones, electrolyte level, the level of the drugs that the patient is using, electrocardiogram and kidney and liver function tests.

Treatment begins with discontinuation of the drugs, associated with serotonin syndrome. Often, this can effectively treat the mild symptoms of the condition. However, its severe cases would require hospitalization of the patient, and administration of certain specific medications. The most commonly used medications to treat symptoms of this condition are, serotonin antagonists like, cyproheptadine and drugs for controlling blood pressure and heart rate. Benzodiazepines are used to relax muscle stiffness and control agitation and seizures. In the meantime, intravenous fluid administration can be required, depending on the severity of the condition.

The main risk factor is taking more than one medication that can increase the level of serotonin in the body. So, the condition can be prevented by taking such serotonergic medication in appropriate dosage, as per the direction given by the physicians. At the same time, people taking such medications should closely watch for its symptoms. If the symptoms look a bit alarming, then a physician should be informed as soon as possible to avoid the complications associated with high serotonin levels in the body.