Introduction
Schizophrenia is a typical brain condition that primarily impairs a person’s ability to think, behave, and perceive the world around them. People with schizophrenia are more likely than the general population to have a distorted perspective of reality. They frequently claim to overhear or witness things or objects that are not there, communicate in a disorderly or unusual manner, believe they are under continual surveillance, and believe that people are attempting to injure them(Miller & Black, 2019). This step makes it challenging to handle routines of daily living, and as a result, these individuals may choose to retreat from the entire world or behave out of panic and perplexity. Even though schizophrenia can be a chronic brain-based condition, its treatments are accessible. People with schizophrenia could operate independently and lead productive lives if they received the appropriate medicine, assistance, and treatment. This paper will discuss three neurochemical-based theories associated with schizophrenia and two medications prescribed to control schizophrenia.
In addition to impairments involving cognition, feelings, and conduct, schizophrenia is connected with different problems. Symptoms and indications are often distinct, indicating a diminished potential to function excellently. They might feature slurred speech and disordered thinking or reasoning. A disorganized way of thinking results in an overall messy way of speaking (Hartman et al., 2019). As a result, an individual’s ability to communicate effectively is impaired, and they provide irrelevant responses to the questions. In some instances, incorporating meaningless phrases into a statement is necessary to comprehend it. This step is usually referred to as “word-based salad,” which different people have described in numerous ways. Hallucinations frequently entail hearing or seeing events that are not there. However, those with schizophrenia remain highly potent and possess the same effect as a usual episode. Hallucinations can express themselves in various ways, with hearing voices appearing to be the most prevalent.
Individuals with schizophrenia must meet the requirements set out by the DSMMD institute for them to get diagnosed. Thus, to assist mental health professionals in identifying and treating psychological conditions, the American-based Psychiatric Association issued this manual(McCutcheon et al., 2020). If schizophrenia is suspected, the healthcare professional should rule out any other metal-based health illnesses and prove that the recorded symptoms are not caused by drug prescriptions, substance misuse, or a widespread medical disease before making the diagnosis (McGuinness et al., 2022). Furthermore, a person must exhibit at least three of the symptoms listed most of the period in a month to qualify. At the minimum, hallucination, illusions, or disorganized speech must be among the signs and symptoms.
Neurochemical Theories Associated with Schizophrenia
The dopamine theory regarding schizophrenia, the serotonin theory of depression, and the glutamate theory will get discussed in detail in this paper. The dopamine hypothesis of schizophrenia holds that the overall neurotransmitters associated with dopamine are to blame for the condition (Pinkham et al., 2020). Dopamine is produced in excess when neurons fire or send too many impulses. Many investigations and a wealth of research work have been done on this are among the most accepted biological ideas. Among the most significant discoveries had been in the study of Parkinson’s disease patients (Stahl, 2018). When antipsychotics were used to treat or cure schizophrenia, several patients developed Parkinson-like uncontrolled convulsions and overall movements. Afterward, it was discovered that Parkinson-affected patients who received massive doses of a medication rich in dopamine exhibited psychotic-schizophrenic symptoms or episodes. L-dopa, a medicine that boosted dopamine amounts so much that it triggered psychosis within patients, was the culprit (Braun et al., 2021). To put it another way, if you want to get rid of the psychiatric symptoms but still have tremors, you’ll need to take a dopamine-blocking medicine. This step implies that schizophrenia is strongly linked to dopamine.
Thus, this hypothesis has been supported by several other investigations of the drug amphetamine. Such medications work by increasing the amount of dopamine inside the brain, stimulating the central-based nervous system. A condition known as amphetamine psychosis could result from excessive use of stimulants (Huang et al., 2020). As a consequence of this finding, dopamine may be involved with all symptoms and psychosis surrounding schizophrenia. Besides, the brains of deceased people with schizophrenia have been studied further, and some contain more dopamine-based transmitters than non-schizophrenic individuals(Abi-Dargham, 2020). However, the drugs they were taking throughout their existence seemed to impact this conclusion. Patients treated with drugs that affect dopamine amounts and receptors provide compelling evidence (Millard et al., 2021). Despite its lack of comprehensiveness, the dopamine hypothesis most likely plays a significant part in the overall picture of schizophrenia. According to one neurochemical concept, producing more of the neurotransmitter dopamine may contribute to some signs and symptoms underlying schizophrenia. Antipsychotic drugs, which can be used in treating schizophrenia, have been shown to reduce dopamine activities within the brain, as supported by various evidence.
Depression and severe symptoms are associated with overall serotonin dysregulation, which may explain why persons with schizophrenia experience such a high incidence of widespread depression and painful symptoms. Thus, to substantiate this step, it has been discovered that selective serotonin-based reuptake inhibitors termed (SSRIs) are beneficial in curing the unpleasant symptoms of schizophrenia (Ramírez et al., 2018). It has been consistently demonstrated that acute tryptophan deprivation, and overall dietary treatment that affects brain-based serotonin (5-HT) manufacturing, might exacerbate negative feelings.
When comparing patients with schizophrenia versus those who do not have schizophrenia, proof of medium to reasonably high quality indicated that higher prefrontal-based serotonin 5-HT1A transmitters had a standard size impact on their symptoms. In addition, research of reasonable quality discovered a low to a significant effect of diminished prefrontal-based serotonin 5-HT2A transmitters in persons with schizophrenia. Regarding the serotonin concept of depression, most symptoms of depression are produced by a lack of serotonin within the brain (Ramírez et al., 2018). This act is an excellent neurochemical hypothesis that has been proven to be true. It has been demonstrated that antidepressant drugs used in treating depression function by raising the amount of serotonin inside the brain cells, which lends weight to this notion.
The glutamate theory of schizophrenia has been based on a lack of glutamate action at the entire glutamate synapse, which is particularly prevalent throughout the prefrontal brain. Dopamine either suppresses glutamate production in several brain locations, or glutamate stimulates neurons which dopamine suppresses in other brain regions (Uno & Coyle, 2019). Glutamate transmission abnormalities caused by NMDA transmitter (NMDAR) dysfunction are thought to be causally related to the severe and positive symptoms of surrounding schizophrenia, as described by the glutamate theory. There is still much to learn about the molecular principles accountable for the altered glutamate transport during schizophrenia (Stahl, 2018). The most significant regulatory glia, the astrocytes, regulate glutamate synthesis and glutamate transportation throughout the brain. The glutamate concept has made tremendous contributions to our knowledge of schizophrenia and other mental illnesses(McCutcheon et al., 2020). Astrocytes control glutamate metabolic action and modify glutamate transmissions in various essential ways, even though glutamate transport is coordinated by ionotropic-based glutamate transmitters and incorporates other pre-existing and postsynaptic elements at synaptic vesicles.
Two Medications Prescribed to Manage Schizophrenia
Antidepressant medications and antipsychotic medications are the two medications prescribed to manage or control schizophrenia. Further, the two medications are explained in detail below and how they link with the theories mentioned earlier in conjunction with supporting evidence.
Antidepressants Medications
In addition to the symptoms associated with schizophrenia, many persons who suffer from it also suffer signs of depression. Overall, antidepressants, which change neurochemicals that are associated with emotions, could be prescribed by doctors to alleviate these observed symptoms (Stroup et al., 2019). Strict serotonin reuptake-based inhibitors (SSRIs), perhaps the most commonly prescribed forms of antidepressants, fall among the most effective treatments for depression. Because teenager-based depression seems to be a severe medical illness that causes chronic feelings of melancholy and losing interest in previously enjoyed activities, antidepressant drugs might have unwelcome side effects. The serotonin theory is linked with this type of medication since it offers the best drugs to handle schizophrenia.
Depression is frequent in patients with schizophrenia, and the disorder has been related to a wide range of difficulties, albeit with a higher risk of death in certain circumstances. Thus, to cure depression, many practitioners employ antidepressant medications in conjunction with antipsychotic drugs. The researchers revealed randomized controlled studies in which antidepressants were compared to persons who seemed to have schizophrenia and experienced depression (Dondé et al., 2018). However, because of the limited studies that provided usable information and the low quality of those research, the evidence for antidepressants’ ability to enhance overall results must be regarded with care. There seems to be no compelling proof either in favor or opposition to the utilization of antidepressants in treating depression in patients with schizophrenia. It is necessary to do additional well-designed, performed, and documented studies within this field.
Depression and other mental disorders seem to be quite widespread because it causes serious health concerns among individuals and adverse educational outcomes. Multiple reports have suggested that the high frequency of the disease and the negative consequences are recurring problems. Furthermore, the number of people claimed to have received a mental health diagnosis in under a year has increased steadily. Similarly, the frequency of therapy among teenagers who suffer from severe depression or other depressive disorders is relatively low. A prescription for antidepressant medicine is given to patients suffering from depression. It works by raising the amount of serotonin within the brain. Thus, an abundance of research-based evidence has been conducted to demonstrate the effectiveness of antidepressant medications in treating depression.
Antipsychotic Medications
Treating schizophrenia and several other mental diseases using antipsychotics has long been considered conventional and first-line proof-based practice. Antipsychotic pharmaceuticals are primarily medicated drug prescriptions that are used in managing the symptoms of schizophrenia by interfering with the dopaminergic neurotransmitter inside the brain (Martino et al., 2018). This step means that they aim to control the early symptoms and signs of schizophrenia rather than cure them. Because patients with schizophrenia react differently to antipsychotic medications, multiple treatment approaches are used. As previously stated, amongst the most important treatment methods for antipsychotics encourages the establishment of sleeping by inhibiting the action of the wake-promoting overall neurotransmitters.
It is possible to utilize antipsychotics to induce sleep amongst schizophrenia-affected patients via the action of neurotransmitters like serotonin type 2 transmitters and dopamine transmitters, among several other things. According to healthcare professionals, these drug treatments assist antipsychotic consumers in falling asleep. Some other Antipsychotics therapeutic strategies enhance alertness through the habitability of metabolic activity in the awake state of consciousness. The wake-based promotion is employed as therapy for various mental illnesses.
When it comes to the pharmacological considerations associated with the antipsychotic’s treatment processes – sleep-wake impacts – various elements are taken into account, including the dosages, drug half-life, and medication-based time intensity. There are a variety of adverse effects associated with this therapy technique; for example, sleep activation medications might lead victims to feel drowsy throughout the daytime (Martino et al., 2018). Antipsychotic drugs have a negative impact mainly on a patient’s ability to operate normally; as a result, they might harm the treatment process for schizophrenia, including psychological interventions. Patients with schizophrenia could get cured with “long-acting injectables,” injections administered every two to three weeks, depending on the medications used. Patients who can follow medical instructions are more likely to benefit from the injectable technique. Paliperidone and Fluphenazinedecanoate are just a few commonly administered drugs through injection. The antipsychotic medication gets used to cure schizophrenia, and the medication functions by decreasing the amount of dopamine inside the brain’s circuits and neurons. Antipsychotic drugs are productive in managing schizophrenia, and there is substantial evidence or proof to support this claim.
Conclusion
In conclusion, this paper examined the dopamine theory of schizophrenia, glutamate theory, and the serotonin theory of depression as three neurochemical-based theories. By illustrating how an antidepressant and antipsychotic drugs function to inhibit the function of dopamine within the brain and raise the quantity of serotonin, correspondingly, these hypotheses were connected to pharmaceutical action. Both antipsychotics and antidepressants are highly productive in managing their related illnesses, and the proof continues to mount. People with schizophrenia have a promising future because recent advancements in treatment have become better every day.
Interventions that work are readily available, and more are being developed. Several people with schizophrenia can return to everyday life and have a fulfilling, independent life. Thus, healthcare professionals and researchers are doing extensive studies to learn about the disorder’s underlying causes and develop methods for predicting and preventing it. Therefore, to assist people with schizophrenia to attain their full potential. Indeed, those who care for someone with schizophrenia are urged to engage in clinical-based trials.
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