Mesoridazine: characteristics and side effects

This type of antipsychotic can cause severe side effects.

There are different types of antipsychotics. These can be classified according to their time of appearance (first or second generation; typical and atypical) and according to the class of drugs to which they belong.

In this article we will discuss one antipsychotic in particular: mesoridazine, belonging to the phenothiazines (a group of antipsychotics).. We will learn about its characteristics, what it is used for and its therapeutic and adverse effects.

Antipsychotic drugs

Before going into mesoridazine, which is an antipsychotic, we will explain in brief what exactly these drugs are. Antipsychotics are drugs, as their name suggests, which relieve psychotic symptoms, such as hallucinations or delusions.. However, they are often also used to treat other symptoms, such as agitation or excessive restlessness.

This is why they are often prescribed to people suffering from psychotic disorders (e.g. schizophrenia), but also to people suffering from confusion, delirium, agitation, movement disorders and tics (e.g. Gilles de la Tourette), etc.

Its mechanism of action involves a blockade of the receptors for dopamine, which causes the levels of dopamine in the brain to decrease.This causes the levels of this neurotransmitter to decrease (people with schizophrenia have been observed to have abnormally high levels of dopamine).

Specifically, antipsychotics block a receptor called D2, which affects four brain pathways: mesolimbic, nigrostriatal, mesocortical and tuberoinfundibular.. Blocking these four pathways produces different adverse effects, but also the desired therapeutic effects (the latter by blocking the mesolimbic and mesocortical pathways).

Now we are going to talk about mesoridazine, a type of antipsychotic drug belonging to the phenothiazines (a chemical compound).

Mesoridazine

Mesoridazine (trade name: Serentil) is an antipsychotic (neuroleptic) drug, which is used for the treatment of schizophrenia to relieve symptoms such as hallucinations, delusions and agitation.

Specifically, mesoridazine is a piperidine neuroleptic (a type of organic compound), and belongs to a class of drugs: the phenothiazines. In turn, it is a metabolite of thioridazine (another typical piperidine antipsychotic drug).

On the other hand, it should be noted that mesoridazine is not currently marketed worldwide. This was withdrawn from the market in the United States in 2004 due to its side effects, which proved to be dangerous.in the United States in 2004 because of its side effects, which turned out to be dangerous.

These effects included: irregular heartbeat and prolongation of the QT interval of the electrocardiogram. It should be noted that the prolongation of the QT interval can generate ventricular arrhythmias in the patient.

Indications

The main indication for mesoridazine is schizophrenia.. It is used, as we have seen, to treat its associated symptoms, which are: hallucinations, delusions and agitation.

Thus, mesoridazine is effective in treating psychotic symptoms, but also other symptoms such as agitation, restlessness or tension, symptoms more typical of schizophrenia disorders.symptoms more typical of anxiety disorders.

Effects on the brain

Mesoridazine has different effects on the brain: antidopaminergic (resulting in a decrease in dopamine), central antiadrenergic (decrease in adrenaline), antiserotonergic (decrease in serotonin) and muscarinic anticholinergic (the latter, weak) effects.

Phenothiazines

We have seen that mesoridazine belongs to the phenothiazine class of drugs. Mesoridazine is included in this group together with other drugs such as: piperacetazine, pipoptiazine, propericiazine, sulforidazine and thioridazine.

But what exactly are phenothiazines? They are a chemical compound, yellowish/greenish in color. Its structure is made up of three rings; specifically, its tricyclic nucleus is made up of two benzene rings, a sulfur atom and a nitrogen atom..

Thus, phenothiazines are actually considered a group of antipsychotics. These in turn are divided into three subgroups (which differ in their chemical structure and pharmacological properties): piperidines, piperazines and aliphatic compounds. Mesoridazine in particular belongs to the first group, the piperidines (as we have already seen).

Dosage and format

Mesoridazine is marketed in different formats: injection, liquid concentrate and tablets. Mesoridazine is generally taken in tablet form, but this will vary depending on the patient.but this will vary depending on the patient (patient profile and needs).

Normally, it is recommended to take it concentrated in water or with orange juice. If mesoridazine is taken as an injection, it is recommended to rest for at least half an hour after administration.

Doses should be prescribed by the physician.The doses should be prescribed by the doctor, who generally prescribes regular and daily doses. It is important not to stop taking mesoridazine (as well as most drugs) suddenly, much less without consulting a specialist; doing so may worsen pre-existing symptoms.

Side effects

Like most drugs, mesoridazine also has side effects. The most common are: weight gain, restlessness, anxiety, constipation, headache, diarrhea, nausea, dizziness, vomiting and changes in appetite.

More serious effects

The effects mentioned above are the most frequent, although if other more serious effects appear, it is important to see a specialist as soon as possible, it is important to see a specialist as soon as possibleWe are talking about symptoms such as (these are only some of them):

• Changes in vision
• Confusion
• Difficulty in breathing or swallowing.
• Darker colored urine (e.g. brown)
• In women: breast milk production (when not breastfeeding)
• Enlarged nipples or breasts
• Mood changes (e.g. depressive and/or anxious symptoms)
• Behavioral changes
• Chest pain
• Irregular or rapid heartbeat
• Fever
• Increased thirst
• Seizures
• Etc.

Other serious side effects

On the other hand, special mention should be made of three serious side effects that can be caused by mesoridazine: akathisia, tardive dyskinesia and neuroleptic malignant syndrome (NMS). These consist of:

1. akathisia

Akathisia, one of the possible side effects of mesoridazine, is the inability to hold still. consists of the inability to keep still together with a feeling of restlessness..

2. Tardive dyskinesia

Tardive dyskinesia is a very typical side effect of antipsychotics. It consists of a movement disorder, which encompasses a series of symptoms mainly involving involuntary movements.

3. Neuroleptic Malignant Syndrome (NMS)

Finally, the Neuroleptic Malignant Syndrome includes symptoms such as stiffness, fever, dyspnea and arrhythmias.. It is a very serious but rare syndrome, which can result in death, lasting 5 to 15 days if not death.

MNS can be caused by multiple antipsychotics, not just mesoridazine.

Bibliographic references:

• Stahl, S.M. (2002). Essential psychopharmacology. Neuroscientific bases and clinical applications. Barcelona: Ariel.
• Vogel, M., Leon, F., Torres, R.& Crossley, N.A.. (2017). First- and second-generation antipsychotics in schizophrenia: efficacy, effectiveness, and effect of dose used. ARS MEDICA, Journal of Medical Sciences, 42(1): 41-48.