Drug-induced Serotonin syndrome and management

The management of serotonin syndrome depends on the severity of the disease. In the case of mild manifestations, the management is simply discontinuing the suspected drug and monitoring the patient's condition. Usually, the symptoms of this syndrome go away after 24 hours. If the early gastrointestinal poisoning before 6 hours, it is possible to perform gastric lavage method, give activated charcoal to remove drugs that cause serotonin syndrome.

Serotonin syndrome is a reaction of drug poisoning due to the accumulation of too much serotonin in the body. Serotonin is considered a neurotransmitter, it is essential for the functioning of nerve cells in the brain. When serotonin levels in the body increase too much, it can cause drug-induced Serotonin syndrome. Manifestations of this syndrome will depend on different levels. Severe cases can be life-threatening.
The main cause of serotonin syndrome is medication. Some drugs, when combined with each other or used in excess, will lead to an increase in serotonin levels in the body. Medications that cause serotonin syndrome may include:
Antidepressants: These include selective serotonin reuptake inhibitors; serotonin-norepinephrine reuptake inhibitors group (duloxetin, venlafaxine...); tricyclic antidepressants (amitriptyline, desipramine, doxepin) and monoamine oxidase inhibitors. Other drugs that cause serotonin syndrome include: Triptans to treat migraines, opioid pain relievers, cough medicines, metoclopramide antiemetics, hallucinogens. In the case of normal and constant levels of serotonin in the blood, it will not cause any special symptoms. However, higher than normal levels of serotonin lead to a range of symptoms ranging from mild to severe, depending on the level of this substance. The most common symptoms are:
Confusion, excitement, excitement, dizziness; Appear hallucinations, more severe may convulsion, coma; There are neuromuscular symptoms such as twitching and jerking, increased tendon reflexes, incoordination, nystagmus, tremor, Babinski's sign; In addition to the above symptoms, the disease also causes symptoms such as high fever; sweating; heart palpitations; hypertension ; dilated or absent pupillary reflex, dilated subcutaneous vessels, increased salivation; pain; throbbing epigastric region. More dangerously, the patient can go into a deep coma, drop blood pressure and lead to death.

Diagnosis of drug-induced serotonin syndrome is usually clinical. Because plasma serotonin levels will usually not be associated with symptoms. For differential diagnosis as well as assessment of complications caused by this syndrome, the following additional tests may be ordered as needed:
Complete blood count, electrolytes, blood culture, analysis and water culture urine. In some cases, routine chest x-ray, ECG, analysis of cerebrospinal fluid, CT scan of the brain are necessary. Clinically, however, the Hunter criterion is most commonly used in the diagnosis of serotonin syndrome. The Hunter criterion is generally more sensitive and specific than the Sternbach criterion. The hallmark symptoms of this criterion are:
Spontaneous Clonus; Clonus due to irritation and agitation or increased sweating; nystagmus and arousal or hyperhidrosis; Run and increase reflexes; Increased muscle tone and body temperature above 380C, with nystagmus or arousal clonus.

Management of drug-induced serotonin syndrome depends on the severity of the disease. In the case of mild manifestations, the management is simply discontinuing the suspected drug and monitoring the patient's condition. Usually the symptoms of this syndrome go away after 24 hours. If the early gastrointestinal poisoning before 6 hours, it is possible to perform gastric lavage method, give activated charcoal to remove drugs that cause serotonin syndrome.
In addition, it is necessary to provide supportive treatment by ensuring oxygen supply and intravenous fluid replacement in case of hypovolemia and hyperthermia. Simultaneously monitor cardiovascular signs through monitoring and use the following measures:
Sedation In case the patient is too agitated, good sedation should be performed instead of immobilizing the patient in bed, this can This can lead to muscle contractions, which in turn can lead to hyperthermia and severe lactic acidosis.
For sedation for patients, it is necessary to use benzodiazepines to control stimulant symptoms, as well as to help reduce blood pressure and heart rate in mild cases. The usual dose of intravenous benzodiazepines is diazepam 5-10mg or lorazepam 2-4mg, repeated every 8-10 minutes based on patient response. Note that butyrophenones should be avoided because these drugs have anticholinergic effects, thereby reducing sweating, making it difficult to handle hyperthermia.
Stabilization of autonomic symptoms If blood pressure and heart rate fluctuate greatly, stabilization of autonomic symptoms can be difficult. Therefore, in cases of high blood pressure as well as a severe increase in heart rate, fast-acting drugs should be used.
However, in the case of low blood pressure, it should be treated with direct sympathomimetic amines such as phenylephrine, epinephrine, norepinephrine, but with caution to avoid indirect drugs, because these drugs are converted to epinephrine. and norepinephrine, under the effect of monoamine oxidase inhibition, the production of epinephrine and norepinephrine cannot be controlled, thus easily causing hemodynamic disorders in patients.
Controlling hyperthermia in patients Hyperthermia in serotonin syndrome is caused by excessive muscle activity, so antipyretic drugs such as paracetamol do not play a role. In case the body temperature is above 41.1 degrees Celsius, it is necessary to be sedated, muscle relaxant and intubated with proper technique. Etomidate (0.3mg/kg IV) and succinylcholine (1.5-2mg/kg IV), but succinylcholine should not be used in patients with hyperkalemia. After intubation, muscle relaxation should be maintained with verocunium and effective sedation.
Active and effective body temperature control will help reduce the risk of serotonin syndrome complications such as seizures, coma, hypotension, metabolic acidosis, tachycardia,...
Use Use of Antidote (Cyproheptadine) In cases where benzodiazepines and supportive measures do not respond, cyproheptadine should be used. Cyproheptadine is a histamine-1 receptor antagonist with nonselective antagonistic activity on both 5-HT2A and 5-HT1A receptors.
Besides, Cyproheptadine also has a sedative effect, but it can also cause transient hypotension in patients. The reason it can cause hypotension is that it can reverse the effects of serotonin on vascular tone. To control this side effect, intravenous fluid replacement is often used.

In summary, serotonin syndrome is a clinical syndrome with diverse manifestations, some cases can affect the patient's life. Therefore, it is necessary to pay attention and be careful with this syndrome when using drugs that affect the serotonergic system, adhere to the principles of dosing as well as avoid the combination of many drugs at the same time because it can lead to the syndrome. this. In case of suspected serotonin syndrome, it is necessary to go to a reputable hospital for timely examination and treatment. Currently, Vinmec International General Hospital is one of the leading prestigious hospitals in the country, trusted by a large number of patients for medical examination and treatment. Not only the physical system, modern equipment: 6 ultrasound rooms, 4 DR X-ray rooms (1 full-axis machine, 1 light machine, 1 general machine and 1 mammography machine) , 2 DR portable X-ray machines, 2 multi-row CT scanner rooms (1 128 rows and 1 16 arrays), 2 Magnetic resonance imaging rooms (1 3 Tesla and 1 1.5 Tesla), 1 room for 2 levels of interventional angiography and 1 room to measure bone mineral density.... Vinmec is also the place to gather a team of experienced doctors and nurses who will greatly assist in diagnosis and detection. early signs of abnormality in the patient's body. In particular, with a space designed according to 5-star hotel standards, Vinmec ensures to bring the patient the most comfort, friendliness and peace of mind.