Quetiapine: Operation And Side Effects Of This Drug
Haloperidol, chlorpromazine, clozapine, risperidone, olanzapine, ziprasidone or quetiapine are the names some of the most well-known and used antipsychotics or neuroleptics These are substances that help keep the symptoms of various mental disorders under control, especially schizophrenia and other psychotic disorders.
In this article Let’s talk about the last of those mentioned, quetiapine to see what type of substance it is, in what cases it is used and its possible side effects.
As indicated in the introduction, quetiapine is a medication with psychoactive effects that is included in the atypical antipsychotics It is a dibenzothiazepine-type substance, being structurally closely related to olanzapine and especially to clozapine.
Its mechanism of action is based on its effects on dopaminergic and serotonergic receptors acting by blocking dopamine D2 receptors in the brain and serotonin receptors (which also reduces, resulting in a general level of dopamine level in most cortical structures being maintained as it is inhibitory to dopamine). ).
This is a great advantage, since It is common that in schizophrenia there is an excess of dopamine at the mesolimbic level and a deficit of this in the mesocortical pathway, respectively generating positive symptoms (hallucinations, delusions, aggression, impulsivity and disorganization) and negative symptoms (alogia and avolition, among others). If we only try to reduce dopamine, as typical antipsychotics do in a way that is not specific to the area to be treated, it would not be working and could even worsen the existence of negative ones, in addition to generating alterations in other areas with higher levels. normative.
In addition to its effect on dopamine and serotonin, It also has histaminergic and cholinergic effects , affecting and reducing the levels of both. This last factor causes some drowsiness and weight gain, as well as hypotension and some physiological and memory alterations.
Quetiapine has a great advantage over other antipsychotics, and that is that it generally does not generate any type of motor side effect. It is because of that Subjects with psychotic problems who also suffer from Parkinson’s can take it (as long as there is no dementia), and which is usually given as a drug to replace treatment with clozapine or olanzapine when extrapyramidal side effects occur. There are also usually no sexual effects, not altering prolactin levels. This indicates that its action at the nigrostriatal and tuberoinfundibular level is minimal, generally not causing effects on the dopamine levels of these pathways.
Main indications and uses
Quetiapine is a very useful psychotropic drug for a large number of people, being used in clinical practice in different disorders and problems. The most common are the following.
1. Schizophrenia
The main and best-known indication for quetiapine is schizophrenia In this sense, quetiapine shows a great effect in the treatment of both positive symptoms (understood as those that add characteristics and/or generate an increase in activation, such as hallucinations and delusions) and negative ones (the opposite, as occurs in poverty of thought and/or speech).
2. Other psychotic disorders
Although schizophrenia is the primary target of most antipsychotics, it is not the only psychotic-type disorder that exists. People with disorders such as brief psychotic disorder, schizophreniform disorder, schizoaffective disorder and chronic delusional disorder may also benefit from the action of quetiapine.
Some second-generation antipsychotics, including quetiapine, have been used in the treatment of manic episodes occurring in subjects with bipolar disorder And not only in the treatment of crises, but also sometimes prophylactically to prevent them from happening. In addition, it also reduces the symptoms of depressive episodes that occur in this same disorder.
4. Major depressive disorder
Since 2010, Quetiapine has been approved for use in the treatment of major depressive disorder in some countries Although it is not the most recommended treatment, it is an alternative that has proven effective in cases of depressed subjects for whom conventional antidepressants do not have an effect.
Side effects and contraindications
As with other drugs, The consumption of quetiapine can lead to a series of undesirable side effects For this reason, among other things, its use must always be indicated and supervised by specialized doctors.
The most common side effect common to all antipsychotics is the possible sedation or drowsiness of the subject, along with weight gain Hypotension and possibly tachycardia are also common, so special caution should be taken in patients with cardiac problems. Also hyperglycemia, and sometimes it can contribute to the appearance of diabetes (you must be especially careful and go to the doctor if you experience extreme thirst or hunger, excessive increase in the urge to urinate or weakness, fruity breath or metallic taste as it could be symptom of ketoacidosis that could become life-threatening due to excess blood sugar).
Problems such as constipation, dry mouth and blurred vision , along with dizziness and hyperthermia, are also relatively common. Due to its anticholinergic action, it can also cause memory impairments. Although it occurs in very few cases, it can cause jaundice, endocrine problems and epileptic seizures. Asthenia, nervousness, akathisia, dryness and liver disorders may also occur.
In severe cases, fever, bleeding, falls, seizures, priapism may occur , tachycardia or breathing difficulties. Also allergies and inflammation of the liver. Finally, the possibility of neuroleptic malignant syndrome arising must be taken into account (which is why the doctor largely regulates the dose and tends to increase it very little by little until the intended levels are reached).
Contraindications
Regarding contraindications, quetiapine is contraindicated in all patients who suffer from heart problems or vulnerability to suffering from them. It is also contraindicated in diabetic subjects, due to weight gain and glycemic level gain, as well as the metabolic alterations it can produce.
Those subjects who require the use of other drugs (especially cytochrome P450 3A4 inhibitors present in some medications for HIV or erythromycin, for example) should not consume quetiapine and should consult with their doctor.
Finally, pregnant and lactating mothers should be very careful You should not drive or operate heavy machinery while under the influence, especially due to the sedation it can cause.
