Serotonin is a neurotransmitter that plays an important role in human functioning. It is mainly responsible for regulating mood and well-being, and has many other important functions. It is often colloquially referred to as the happiness hormone. If the body lacks serotonin for various reasons, it can cause anxiety or depression, among other things.
However, if there is an excess of serotonin in the body, life-threatening serotonin syndrome can result. Learn more about serotonin syndrome, check out what drugs it can occur after and what is the treatment?
How does serotonin work?
Serotonin is a neurotransmitter that transmits signals between nerve cells (neurons) in the brain. It plays a key role in regulating many physiological and psychological processes. Serotonin has both peripheral and central actions in the body. For peripheral action, serotonin is produced by specialized endocrine cells of the gastrointestinal tract. It stimulates contractions of the uterus, blood vessels, bronchi, and aids the clotting system.
In the case of the central nervous system, it affects behavioral changes. Affective behaviors such as anxiety and depression, insomnia, and attention. In addition, it has a tremendous impact on libido, mood, appetite and the body’s heat metabolism. Consequently, its presence is essential for proper human functioning. Deficiencies of serotonin can be associated with increased appetite, depressive and anxiety disorders, headaches, anxiety, decreased concentration, irritability, memory deterioration and trouble sleeping. It is excess serotonin, however, that is most dangerous to humans.
What is serotonin syndrome?
Serotonin syndrome (SS), otherwise known as serotonergic syndrome, is a drug-induced syndrome caused by an excess of serotonin in the central nervous system. It results, from excessive stimulation of serotonin receptors in the body. It is a rare but very dangerous complication.
As early as the 1950s, symptoms corresponding to serotonin syndrome were analyzed. With the development of medicine and the advent of new generations of drugs, symptoms of serotonin syndrome were increasingly observed. The late 1980s marked the beginning of an increase in the sale of antidepressant drugs and, consequently, a higher incidence of serotonin syndrome. An important fact is that an excess of serotonin in the body physiologically does not occur, because the body has adequate mechanisms to prevent it. Serotonin syndrome can be triggered only by selected groups of drugs and, less frequently, by certain types of drugs. We can distinguish three forms of serotonin syndrome, listed according to the intensity of symptoms:
- Mild serotonin syndrome-otherwise known as lightserotonin syndrome, due to the small number of symptoms, often goes unnoticed by the doctor and the patient. Usually in its case, it is enough to stop the drugs that caused it, and the symptoms will resolve on their own.
- Acute serotonin syndrome – is characterized by the rapid development of symptoms of severe intensity, the onset of high fever, even above 41 degrees Celsius, and can threaten the health of the affected person. Therefore, this condition often requires hospital treatment and therapy with appropriate measures.
- Malignant serotonin syndrome, with very severe symptoms, can even be life-threatening and requires admission of the sick person to an intensive care unit, and respiratory support with a ventilator.
Causes of serotonin syndrome
Serotonin syndrome can develop in people who take selected types of drugs. However, if the drugs are taken in doses consistent with the doctor’s recommendations, the manufacturer and current medical knowledge, the risk of developing the syndrome is low.
Usually this syndrome, is associated with drug overdose, or combining different types of drugs with the same mechanism of action, that is, polypharmacotherapy causing pharmacodynamic reactions, affecting the increase of serotonin in the body. Taking certain types of drugs, especially in combination with drugs can also promote the development of serotonin syndrome. It can happen that serotonin syndrome occurs in a newborn whose mother during pregnancy took substances or drugs that affect the increase of serotonin in the body.
Serotonin syndrome – after which drugs can occur?
Serotonin syndrome primarily affects people who take antidepressants. Of course, in case they overdose on them, or combine them with drugs with similar mechanisms of action. These are drugs from the SSRI group ( selective serotonin reuptake inhibitors). The effect of these drugs is that they block the transport of serotonin to nerve cells, which causes the concentration of serotonin in the brain itself to increase.
Drugs that can cause serotonin syndrome:
- Drugs from the SSRI group (selective serotonin reuptake inhibitors) – escitalopram, citalopram, fluvoxamine, paroxetine, sertraline, fluoxetine.
- Drugs from the T-LPD group (tricyclic antidepressants) – imipramine, amitriptyline, doxepin, maprotiline, clomipramine.
- Ciprofloxacin – an antibiotic.
- Antiemetics – trazodone, bupropion, ondansetron, metoclopramide.
- OLP (opioid analgesics) – tramadol, pentazocine, fentanyl.
- Drugs from the SNRI group (Serotonin and Norepinephrine Reuptake Inhibitors) venlafaxine, duloxetine.
- Buspirone – a drug used to treat anxiety symptoms.
- Fluconazole – a drug used for ringworm.
- Mirtazapine – an antidepressant drug.
- Dextromethorphan – an antitussive drug.
- Diphenhydramine – a drug used for colds.
- Selegiline – a drug used for Parkinson’s disease.
- Triptans – medication used for migraines.
- and others.
Drugs that can cause serotonin syndrome:
- LSD.
- Cocaine.
- Addictive drugs.
- Amphetamine.
- Ecstasy.
In addition, it should be noted that long-term alcohol consumption increases the risk that the developed serotonin syndrome will have a very severe course. Factors that can predispose to serotonin syndrome include medical conditions such as hypercholesterolemia, hypertension, atherosclerosis and liver diseases that slow down drug metabolism.
Herbal preparations that can cause serotonin syndrome.
Although the syndrome is most often associated with medications, there are also herbal preparations that can increase the risk of developing it, especially when used in combination with other substances that affect serotonin levels.
Names of herbs that can cause serotonin syndrome.
- St. John’s wort (Hypericum perforatum)
Mechanism of action: St. John’s wort is known for its antidepressant properties and may act as a serotonin reuptake inhibitor (SSRI), increasing serotonin levels in the brain.
Risks: on its own, it rarely causes serotonin syndrome, but when combined with other serotonergic drugs (e.g. SSRIs, SNRIs, MAOIs), the risk increases significantly.
- Panax ginseng (ginseng)
Mechanism of action: ginseng can affect serotonergic neurotransmission.
Risks: there are reports of cases of serotonin syndrome with concurrent use of ginseng and drugs that affect serotonin levels.
- Gingko biloba
Mechanism of action: Gingko biloba can affect neurotransmitters, including serotonin.
Risks: The risk is low, but use in combination with other substances that affect serotonin may increase the risk of serotonin syndrome.
- Ephedra (Ephedra sinica)
Mechanism of action: ephedra affects the release of monoamines, including serotonin.
Risks: there are reports of cases of serotonin syndrome as a result of ephedra use, especially in combination with other serotonergic drugs.
- Synephrine (from Citrus aurantium)
Mechanism of action: synephrine is a chemical compound similar to ephedra and can affect the serotonergic system.
Risks: in combination with other serotonin-enhancing substances, it may increase the risk of serotonin syndrome.
- Muira puama
Mechanism of action: may affect the serotonergic system through its adaptogenic properties.
Risks: reports are limited, but theoretically there are risks when combined with other serotonergic substances.
- Nutmeg (nutmeg)
Mechanism of action: high doses of nutmeg may affect the serotonergic system.
Risks: when consumed excessively in combination with other drugs, it can theoretically increase the risk of serotonin syndrome.
Symptoms of serotonin syndrome
Serotonin syndrome can be characterized by a wide range of symptoms. The onset of serotonin syndrome is usually sudden. Early recognition of serotonin syndrome reduces the risk of dangerous complications. People who take drugs that affect serotonin in the body should be alert to the symptoms of SS. Unfortunately, there is a specified time frame for the appearance of symptoms since taking the substance.
Symptoms of serotonin syndrome can be divided into three groups: psychological symptoms, somatic symptoms, and those related to the autonomic nervous system.
Serotonin syndrome somatic symptoms:
- Tremor of the limbs, numbness of the limbs, e.g. paresthesias
- Muscle stiffness, muscle tension.
- Unintentional muscle spasms.
- Motor coordination disorders.
- Myoclonic movements.
- Renal failure,
- DIC – disseminated intravascular coagulation syndrome.
- Convulsions.
- Metabolic acidosis.
- Muscle cell breakdown.
- Epileptic seizures.
Serotonin syndrome mental symptoms:
- Hallucinations.
- Anxiety.
- Hypomania.
- Irritability.
- Confusion.
- Coma.
- Psychomotor agitation.
Serotonin syndrome symptoms from the autonomic (vegetative) system:
- Increased sweating.
- Increase in heart rate.
- Increase in blood pressure.
- Nausea.
- Chills.
- Accelerated breathing.
- Diarrhea.
- High body temperature.
Serotonin syndrome – how long does it last?
Symptoms of serotonin syndrome appear relatively quickly, but if left untreated they can persist for a long time. The duration of serotonin syndrome depends on many different factors. The time is influenced by the causes of the syndrome, the treatment taken, the speed with which treatment is taken, and general health. However, usually after the substances that caused serotonin syndrome are discontinued, symptoms disappear within 24 to 72 hours. In more severe cases, where hospital treatment is needed, this time can increase significantly.
How to diagnose serotonin syndrome? Diagnosis of serotonin syndrome
There are no tests or laboratory tests that can conclusively determine the onset of serotonin syndrome. Diagnosis is based on a detailed history taken by the doctor and observation of symptoms. Therefore, it is necessary to answer the doctor’s questions meticulously and with detail, without hiding significant facts. First, the doctor takes a thorough history of the diseases the patient suffers from and the medications, supplements, even herbs, and other psychoactive substances the patient is taking. Patients often conceal the fact that they have been taking psychoactive substances such as drugs in addition to prescribed medications, which significantly complicates and prolongs the diagnosis. Serotonin syndrome, due to its similar symptoms, can be confused with malignant neuroleptic syndrome, alcoholic delirium, metabolic disorders, hyperthermia, anticholinergic syndrome, meningitis, various infections and other conditions. The syndrome can have very similar symptoms to neuroleptic syndrome, but the latter, takes much longer to develop.
Treatment of serotonin syndrome
As a first step, all drugs that have a serotonergic effect should be eliminated and symptomatic therapy introduced. Discontinuation of drugs that caused serotonin syndrome has an effect in up to 70% of patients within 24 hours. Less than half of the patients need several days of hospitalization, and in the most severe cases intensive care unit treatment is necessary. The treatment that characterizes serotonin syndrome, in particular, is to increase fluid intake. To reduce muscle tension, benzodiazepines are administered, which will reduce the risk of more severe symptoms and calm the agitated patient. Sometimes it is necessary to intubate and support breathing with a ventilator in the intensive care unit.
With serotonin syndrome, fever is very common, so in this case, ice packs around the arteries, and antipyretics are recommended – but they have low efficacy in AS. In the case of high blood pressure and heart rate, low-dose hypotensive drugs are used to lower blood pressure. In some cases it will be necessary to use cyproheptadine, a serotonin receptor antagonist. With properly selected therapy that is not applied too late, the risk of death is less than 1%. Serotonin syndrome usually does not carry complications, but sometimes it is diagnosed too late and kidney failure or muscle cell breakdown occurs.
Serotonin syndrome – what to do to prevent it?
There are ways to reduce the risk of serotonin syndrome. Here are the most important of them:
- Read the leaflets that come with the medications you are about to take. This is an extremely important habit that will help you avoid not only the onset of serotonin syndrome, but also other unpleasant consequences of combining certain medications. There are various other important tips on driving, or combining medications with certain foods.
- Recommended dosages, Use medications and herbs as prescribed by your doctor, and remember not to exceed the recommended dosages!
- Inform your doctor about medications you are taking on a regular basis. This will ensure that your doctor is careful not to select medications that cause unwanted interactions with each other.
- Be honest. Do not be ashamed of taking psychoactive substances, during the medical interview. Also, do not hide genetic diseases and other problems.
- Don’t self-medicate, especially when it comes to prescription drugs.
- Be careful with herbal infusions, as they sometimes cause interactions with certain drugs.
- It is worth remembering not to combine medications with psychoactive substances and alcohol, this is extremely dangerous to health and life.
- Early intervention, react. If symptoms of serotonin syndrome occur, immediate medical intervention is key. Symptoms can escalate quickly, so acting quickly can save lives.
Summary
Serotonin is an extremely important neurotransmitter and hormone found in the human body. The body has natural mechanisms to regulate it. The problem arises when there is an excess of it through medications taken or psychoactive substances. Serotonin syndrome, although very dangerous, definitely has a good prognosis. People who take antidepressants are particularly at risk of it.
Promptly noticed and treated, it usually passes within a few days. In order to prevent the onset of serotonin syndrome, it is necessary to pay special attention to ensure that the medications taken do not interact with each other. Therefore, it is best to take medications only under the supervision of a doctor and not to change the dosage or type of medication without prior consultation.
Remember, often drug treatment alone is not sufficient for symptoms of depression or anxiety. Make an appointment for psychotherapy – online psychotherapy
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