The Use of Pharmacology in the Treatment of Mental Health - Report Example

The use of Pharmacology in the Treatment of Mental Health Name Course Name and Code Instructor’s Name Date It is estimated that 12% of the global burden of disease is made up of mental and behavioral disorders. It is also estimated that over 450 million people suffer from diagnosable mental illness and that four out of six leading causes of years lived with disability are caused by neuropsychiatric disorders (Melillo & Houde, 2011). Most patients with mental illness are managed in the community setting. This often places extra demands on primary health practitioners, friends and family (Cohen, 2009). Thus, it has been argued that use of medications is central to effective management of mental illness (Wilbourn & Prosser, 2003). In spite this; evidence has emerged that some psychotropic medications are abused. They are also associated with some side effects dependent on the age of the patient with the elderly being more vulnerable (van Rijswijk et al., 2007). A review carried out by the World Health Organization (WHO) revealed that mental disorders can best be treated using a combination of psychosocial and pharmacological approaches. This paper discusses the use of pharmacology in the treatment of mental illness. Many drugs have been introduced in the market for treatment of mental disorders. Advances in molecular biology and neuroscience have especially resulted in new medications for treatment of schizophrenia and depression (Cohen, 2009). Rational drug design has been the main mode of designing drugs via the manipulation of chemical structures of drugs (Cranford, Eisenberg, & Serras, 2009). The employment of rational drug design in research is mainly aimed at addressing the side effects that have been associated with mental health drugs (Lovheim et al. 2008). Drugs for mentally ill patients that were introduced in 1960s were mainly discovered by accident and their use was commissioned prior to understanding the mechanism of their action once their safety was established (Melillo & Houde, 2011). Since then much research has been carried out and it has resulted in the elucidation of the etiology of mental disorders and discovery of new pharmacotherapies (Cohen, 2009). Drugs such as lithium for bipolar treatment, chlorpromazine for psychosis and imiprine for depression were some of drugs that were accidentally discovered in 1960s (Wilbourn & Prosser, 2003). The discovery of chlorpromazine and other neuroleptic drugs are said to be some of the forces behind the deinstitutionalization of mentally ill patients. The following table summarizes the pharmacological drugs recommended by WHO for treatment of mental disorders. Drugs Mental disorder Chlorpromazine, fluphenazine, haloperidol Psychotic disorders Amitriptyline, fluoxetine Depressive disorders Diazepam Generalized anxiety and sleep disorders Carbamazepine, lithium carbonate, valproic acid Bipolar disorders Clomipramine Obsessive compulsive disorders and panic attacks Methadone and buprenorphine Substance dependence disorders Mechanisms of Action Another important issue while dealing with mental drugs is the mechanism of action. Mechanism of action refers to how a drug interacts with its target in the body to produce therapeutic effects (Hawkins, 2009). Drugs which act in a similar way are usually grouped together into broad categories such as antidepressants and stimulants (Melillo & Houde, 2011). Each category has various chemical classes. Individual drugs within a chemical class have similar chemical structure. The table below shows some categories of pharmacological drugs used in management of mental disorders. Category Class Chemical class Example Disorder Antipsychotics (neuroleptics) Typical antipsychotics (first-generation antipsychotics) Phenothiazines Chlorpromazine Schizophrenia, psychosis Butyrophenones haloperido Thioxanthenes - Atypical antipsychotics (second-generation antipsychotics) Dibenzoxazepine Clozapine Thienobenzodiazepine Olanzapine Benzisoxazole Risperidone Antidepressants Selective serotonin reuptake inhibitors Depression, anxiety Tricyclic and heterocyclic antidepressants imipramine and amitriptyline Monoamine oxidase inhibitors Stimulants Attention-deficit/hyperactivity disorder Antimanic Lithium Mania Anticonvulsants Thyroid supplementation Antianxiety (anxiolytics) Benzodiazepines Anxiety Antidepressants B-Adrenergic-blocking drugs Cholinesterase inhibitors Alzheimer’s disease Most drugs for mental disorders act either by increasing or reducing the amount of a neurotransmitter (Cohen, 2009). The alteration of the level of neurotransmitters can be attained through various ways such as mimicking the neurotransmitter in cell to cell signaling; altering the synthesis, uptake or degradation of the neurotransmitter or blocking the action of the neurotransmitter (Wilbourn & Prosser, 2003). For instance, the selective serotonin reuptake inhibitors (antidepressants) block the action of the transporter protein for serotonin, which results in accumulation of serotonin at the synapse. The interaction between a pharmacotherapy and a receptor takes place as either an agonist or as an antagonist. In cases where a pharmacotherapy acts as an agonist, it mimics the action of the natural neurotransmitter (Melillo & Houde, 2011). On the other hand, when a pharmacotherapy acts as an antagonist, it inhibits, or blocks, the neurotransmitter’s action, often by binding to the receptor and preventing the natural transmitter from binding there (Wilbourn & Prosser, 2003). Thus an antagonist disrupts the action of the neurotransmitter. There exists a diverse array of receptors (van Rijswijk et al., 2007). This presents many opportunities for developing drugs. Rational drug design has resulted in the development of pharmacotherapies that are highly selective in their actions. The selectivity of the pharmacotherapy determines extent of its side effects, that is, more selective pharmacotherapy has fewer side effects as compared to one which targets several receptors (Cohen, 2009). Thus, narrower pharmacotherapies are more selective and have fewer side effects as compared to broad spectrum pharmacotherapy. Example of pharmacotherapy is antipsychotic for psychosis. Psychosis is a non specific syndrome that is characterized by hallucinations, delusions, bizarre behavior and loss of contact with reality (van Rijswijk et al., 2007). This syndrome may result from primary psychiatric disorders such as schizophrenia, medical disorders and substance abuse disorders (Cohen, 2009). Schizophrenia is the commonest primary psychosis. Antipsychotic agents are primarily used in medication of schizophrenia and related psychotic disorders. Antipsychotic agents are classified as either first generation or second generation antipsychotics (Wilbourn & Prosser, 2003). First generation antipsychotic drugs include phenothiazines, butyrophenones, thioxantenes and the substituted benzamides. Second generation antipsychotics include aripiprazole, amisulpride, clozapine, risperidone, olanzapine, serindole, quetiapine, zotepine and ziprasidone. Clozapibne is more effective for treatment of refractory schizophrenia than first generation antipsychotic (Melillo & Houde, 2011). First and second generation antipsychotic are both effective in the treatment of psychotic symptoms. The WHO recommended antipsychotic drugs include chlorpromazine, decanoate or enantate, haloperidol and fluphenazine . these drugs are recommended because of the available evidence for their effectiveness and safety. It is recommended that treatment be administered under physician observation for six to eight weeks (van Rijswijk et al., 2007). Clozapine is contraindicated as a first line treatment because it may cause life threatening adverse effects such as agranulocytosis. Treatment need to continue for at least one year after resolution of the acute episode psychotic symptoms to avoid relapse of such symptoms (Wilbourn & Prosser, 2003). It has been suggested that one antipsychotic be used at a time since a combination does not provide an added benefit even though they produce additional adverse effect (van Rijswijk et al., 2007). Furthermore high dosages of antipsychotics increase the risk of adverse effect without any added benefit. The side effects of antipsychotic are either neurologic or anticholinergic side effects. The neurologic side effects include acute dystonias such as slow and prolonged muscular spasms; parkinsonian effects such as resting tremor, rigidity and akinesia; akathisia; neuroleptic malignant syndrome,; taditive dyskinesia and convulsions. Anticholinergic side effects include central effects such as severe confusion and agitation and peripheral effects such ad blurred vision, dry mouth, urinary retention and constipation (Cohen, 2009). Apart from antipsychotic, another important drug is that used for treatment of depression. Depression is characterized by episodes of depressed mood which are associated with lowered mood, reduced energy and decreased activity (van Rijswijk et al., 2007). Depression is classified as mild, moderate or severe. Studies have shown that depression is common in women than men. Symptoms associated with depression greatly impair everyday functioning. Antidepressants are classified based on the mechanism of their action (Melillo & Houde, 2011). They include tricyclic or related antidepressants, selective serotonin reuptake inhibitors, and monoamine oxidase inhibitors (van Rijswijk et al., 2007). All of these antidepressants are effective for treatment of acute depression. Amitriptyline and fluoxetine are the WHO recommended drugs for depression because iof their effectiveness and safety (Cohen, 2009). Monoamine oxidase inhibitors are contraindicated for use as a first line treatment because of the risk of significant side effects. Overdose of tricyclic antidepressants are toxic while fluoxetine and other serotonin inhibitors are less dangerous (Wilbourn & Prosser, 2003). Treatment ought to be assessed for its effectiveness for minimum of six to eight weeks. Simultaneous administration of more than one antidepressant does not offer any added benefit but are associated with increased side effects (van Rijswijk et al., 2007). Discontinuation of antidepressant ought to be gradual. Tricyclics are associated with side effects such as sedation, cardiovascular effects, anticholinergic effects, weight gain, narrow angle glaucoma and prostatism (Wilbourn & Prosser, 2003). Selective serotonin reuptake inhibitors side effects include tremor, activation, dizziness, agitation, nausea, insomnia, sexual problems, diarrhea, weight loss, hyponatraemia, rash and headache. Moreover, depressions are associated with disorders and sometimes the drugs used to treat such mental health share similar chemical content. Bipolar are characterized with mania episodes and major depressions. Manic episode refers to persistent elevation of mood, increased activity and energy and marked feeling of well being in addition to both mental and physical efficiency (Melillo & Houde, 2011). Manic episodes are sometimes associated with significant social dysfunction and personal distress. Manic symptoms may result from substance abuse or general medical condition (Wilbourn & Prosser, 2003). The first onset of manic episodes appears between 19 and 29 years. Treatment of bipolar disorders is complicated by medicine and alcohol abuse (Cohen, 2009). In severe cases of manic episodes or marked behavioral disturbances antipsychotic drugs may be administered. For long term management of bipolar disorders lithium is recommended (van Rijswijk et al., 2007). Lithium is associated with side effects such as muscular weaknesses, tremor, polydypsia, polyuria, diabetes inspidus, weight gain, cardiac arrhythmias, sedation, cognitive problems, impaired coordination, hair loss, gastrointeinal distress, benign leukocytosis, hair loss, acne, hypothyroidism and oedema. On the other hand, carbamazepine is associated with side effects such as drowsiness, diplopia, ataxia and nausea. Anxiety is characterized by the subjective and physiologic manifestations of fear. Non pharmacologic treatment is recommended for initial treatment of anxiety. If non pharmacologic treatment is not effective, benzodiazepines is indicated (Cohen, 2009). Benzodiazepines are regulated by the convention on psychotropic substances (Videbeck, 2010). Benzodiazepines hasten onset of sleep, increase total sleeping time, decrease nocturnal awakening and reduce pathological anxiety, tension and agitation (Wilbourn & Prosser, 2003). Benzodiazepines should not be used for more than four weeks since this may induce dependency and withdrawal symptoms. Benzodiazepines are associated with side effects such as sedation, drowsiness, and muscle weakness (Melillo & Houde, 2011). Other side effects include headache, vertigo, confusion, dysarthria, depression, tremor, changes in libido, amnesia and changes in salivation. Withdrawal symptoms of benzodiazepines include depression, anxiety, insomnia, and dizziness, loss of appetite, impaired concentration, tinnitus, perspiration, perceptual disturbances and irritability (van Rijswijk et al., 2007). Treatment of obsessive compulsive disorders and panic attacks Obsessive compulsive disorders are characterized by recurrent obsessional thoughts or compulsive acts. Panic disorders are characterized by recurrent attacks of severe anxiety that are not restricted to specific situation or set of circumstances. The onset of these disorders are between late adolescence and the mid 30s (Cohen, 2009). The first line treatment for these disorders is cognitive behavioral interventions. Clomipramine is the WHO recommended first line drug for treatment of obsessive compulsive and panic disorders (Melillo & Houde, 2011). The recommended second line pharmacological treatment for panic disorder is benzodiazepines (Hawkins, 2009). Cognitive behavioral intervention is recommended to be used hand in hand with the pharmacological intervention (van Rijswijk et al., 2007). The burden of mental disorder is very high globally. Most patients with mental illness are managed in the community setting. A review carried out by the World Health Organization (WHO) revealed that mental disorders can best be treated using a combination of psychosocial and pharmacological approaches. Many drugs have been introduced in the market for treatment of mental disorders. Advances in molecular biology and neuroscience have especially resulted in new medications for treatment of schizophrenia and depression. Most drugs for mental disorders act either by increasing or reducing the amount of a neurotransmitter. Rational drug design has resulted in the development of pharmacotherapies that are highly selective in their actions. The selectivity of the pharmacotherapy determines extent of its side effects, that is, more selective pharmacotherapy has fewer side effects as compared to one which targets several receptors. Thus, narrower pharmacotherapies are more selective and have fewer side effects as compared to broad spectrum pharmacotherapy. Psychosis is treated with antipsychotic drugs such as phenothiazines, butyrophenones, thioxantenes and the substituted benzamides. Depression is treated with drugs such as tricyclic or related antidepressants, selective serotonin reuptake inhibitors, and monoamine oxidase inhibitors. Bipolar disorders are managed with antipsychotic drugs. Anxiety and sleep disorders are managed with benzodiazepines. Clomipramine and benzodiazepines are used to manage obsessive compulsive disorders and panic attacks. In spite these drugs having been approved for use in mangemnet of various mental illnesses, they have various side effects. It is recommended that cognitive behaviporal intervention be combined with the administration of these drugs for best results. Reference Cohen, L. (2009). Pharmacology and treatment of substance abuse: evidence- and outcome-based perspectives. London: Routledge. Cranford, J., Eisenberg, D., & Serras, A. (2009). Substance use behaviors, mental health problems, and use of mental health services in a probability sample of college students. Addictive Behaviors, 34(2), 134-145 Hawkins, E. (2009). A Tale of Two Systems: Co-Occurring Mental Health and Substance Abuse Disorders Treatment for Adolescents. Annual Review of Psychology, 60, 197-227 Lovheim, H., Sandman, P., Kallin, K., Karlsson, S., & Gustafson, Y. (2008). Symptoms of mental health and psychotropic drug use among old people in geriatric care, changes between 1982 and 2000. International Journal of Geriatric Psychiatry, 23(3), 289-294 Melillo, K., & Houde, S. (2011). Geropsychiatric and mental health nursing, 2nd Ed. London: Jones & Bartlett Publishers. van Rijswijk, E., Borghuis, M., van de Lisdonk, E., Zitman, F., & van Weel, C. (2007). Treatment of mental health problems in general practice: a survey of psychotropics prescribed and other treatments provided. Int J Clin Pharmacol Ther., 45(1), 23-9. Videbeck, S. (2010). Psychiatric-Mental Health Nursing, 5th Ed. London: Lippincott Williams & Wilkins. Wilbourn, M., & Prosser, S. (2003). The pathology and pharmacology of mental illness. London: Nelson Thornes. Read More

Drugs such as lithium for bipolar treatment, chlorpromazine for psychosis and imiprine for depression were some of drugs that were accidentally discovered in 1960s (Wilbourn & Prosser, 2003). The discovery of chlorpromazine and other neuroleptic drugs are said to be some of the forces behind the deinstitutionalization of mentally ill patients. The following table summarizes the pharmacological drugs recommended by WHO for treatment of mental disorders. Drugs Mental disorder Chlorpromazine, fluphenazine, haloperidol Psychotic disorders Amitriptyline, fluoxetine Depressive disorders Diazepam Generalized anxiety and sleep disorders Carbamazepine, lithium carbonate, valproic acid Bipolar disorders Clomipramine Obsessive compulsive disorders and panic attacks Methadone and buprenorphine Substance dependence disorders Mechanisms of Action Another important issue while dealing with mental drugs is the mechanism of action.

Mechanism of action refers to how a drug interacts with its target in the body to produce therapeutic effects (Hawkins, 2009). Drugs which act in a similar way are usually grouped together into broad categories such as antidepressants and stimulants (Melillo & Houde, 2011). Each category has various chemical classes. Individual drugs within a chemical class have similar chemical structure. The table below shows some categories of pharmacological drugs used in management of mental disorders.

Category Class Chemical class Example Disorder Antipsychotics (neuroleptics) Typical antipsychotics (first-generation antipsychotics) Phenothiazines Chlorpromazine Schizophrenia, psychosis Butyrophenones haloperido Thioxanthenes - Atypical antipsychotics (second-generation antipsychotics) Dibenzoxazepine Clozapine Thienobenzodiazepine Olanzapine Benzisoxazole Risperidone Antidepressants Selective serotonin reuptake inhibitors Depression, anxiety Tricyclic and heterocyclic antidepressants imipramine and amitriptyline Monoamine oxidase inhibitors Stimulants Attention-deficit/hyperactivity disorder Antimanic Lithium Mania Anticonvulsants Thyroid supplementation Antianxiety (anxiolytics) Benzodiazepines Anxiety Antidepressants B-Adrenergic-blocking drugs Cholinesterase inhibitors Alzheimer’s disease Most drugs for mental disorders act either by increasing or reducing the amount of a neurotransmitter (Cohen, 2009).

The alteration of the level of neurotransmitters can be attained through various ways such as mimicking the neurotransmitter in cell to cell signaling; altering the synthesis, uptake or degradation of the neurotransmitter or blocking the action of the neurotransmitter (Wilbourn & Prosser, 2003). For instance, the selective serotonin reuptake inhibitors (antidepressants) block the action of the transporter protein for serotonin, which results in accumulation of serotonin at the synapse. The interaction between a pharmacotherapy and a receptor takes place as either an agonist or as an antagonist.

In cases where a pharmacotherapy acts as an agonist, it mimics the action of the natural neurotransmitter (Melillo & Houde, 2011). On the other hand, when a pharmacotherapy acts as an antagonist, it inhibits, or blocks, the neurotransmitter’s action, often by binding to the receptor and preventing the natural transmitter from binding there (Wilbourn & Prosser, 2003). Thus an antagonist disrupts the action of the neurotransmitter. There exists a diverse array of receptors (van Rijswijk et al., 2007). This presents many opportunities for developing drugs.

Rational drug design has resulted in the development of pharmacotherapies that are highly selective in their actions. The selectivity of the pharmacotherapy determines extent of its side effects, that is, more selective pharmacotherapy has fewer side effects as compared to one which targets several receptors (Cohen, 2009). Thus, narrower pharmacotherapies are more selective and have fewer side effects as compared to broad spectrum pharmacotherapy.

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