Treatments of Major Depressive Disorder - Research Paper Example

? Treatment of Major Depressive Disorder Introduction Mood disorders are a clinical spectrum of mental disorders which include mainly bipolar mood disorder and major depressive disorder. It is important to correctly diagnose and differentiate between these two disorders because these two illnesses differ in the way they are treated. According to the Diagnostic and statistical manual of mental disorders (DSM-IV-TR), major depressive disorder is a syndrome with five symptoms or more among the following; depressed mood, agitation ,sleep disturbance, anhedonia , loss of appetite, suicidal thoughts, fatigue ,feeling worthless occurring in a two week period (APA, 2009). The first symptoms to appear are the somatic symptoms. The underlying pathology in depression has not been clearly identified but it is believed to arise from a defect in the brain circuits especially those that they mainly the amine neurotransmitters. It’s important for the cause to be discovered to find an exact treatment in line with the pathology; this will have high specificity which will translate to a higher success rate of that treatment. In the 1950s, it was found that the drug reserpine could lead to depression and its mechanism of action was prevention of storage of neuro-transmitters such as norepinephrine and serotonin. This discovery lead to what is now called as the amine hypothesis which indicates that depression is related to decreased amount of neurotransmitters in the synaptic cleft. This evidence is supported by how antidepressants such as the selective serotonin uptake inhibitors effectively treat depression. Although there may be other brain circuits that lead to depression, the amine hypothesis has lead to the discovery of many classes of drugs that treat depression (APA, 2008). Treatment Before initiating treatment the patient should be assessed as a whole and not only as a case because the causes of depression are multifactorial and these etiological factors whether they are inducing factors or stressors must be probed in a through history, physical and mental examination. Findings from the history and the clinical exam will reveal important information such as severity of symptoms, level of functional impairment as in whether the patient can care for himself or not, suicidal thoughts and family support which will influence the treatment plan. The options available to a psychiatrist are pharmacotherapy, psychotherapy and somatic therapies (Reid, 2009). The aim of treatment is to make the patient to lead a normal life and improve its quality .During the acute phase, one can either use only pharmacotherapy or in conjunction with psychotherapy and when the symptoms are very safe use electroconvulsive therapy if it is available. The antidepressants through their mode of action increase the availability of neurotransmitters in the synaptic cleft, this act on the postsynaptic membrane for a prolonged period. They do this by inhibiting the uptake mechanism, antagonizing the receptor sites for neurotransmitter uptake or blocking the enzyme that degrades them. They have shown noteworthy efficacy in treating major depressive disorder and there is evidence for their efficacy as illustrated in a recent meta-analysis with data from January 1980 to march 2009 which used a randomized placebo controlled trials found that in patients with a Hamilton Rating Depression scale of 25,the effects of medication far outweigh the placebo. The benefits of the medication increase with the severity of symptoms and is at best with patients who have severe depression but are no better than a placebo in mild and moderate depression (APA, 2009).There is no major inter or intraclass difference in efficacy across the classes so it’s better to look at adverse effects profile, patients preference and previous treatment. The oldest classes of antidepressants are the tricyclics which have close relations with phenothiazines chemically. They were first thought to be antihistamines until later when their antidepressive effects were discovered .The prototypes of drugs in this group are imipramine (Tofranil) and amitriptyline (Elavil).Their mechanism of action is by inhibiting the norepinephrine and serotonin reuptake pumps. They also have other pharmacological effects which contribute to their side effects such as sedation, tremors, hypotension, arrhythmias, seizures, weight gain, sexual disturbances and the worst adverse effect is that it may lead to suicide ideation (APA, 2009). Selective serotonin reuptake inhibitors (SSRIs) include citalopram (celexa), fluoxetine (Prozac), fluvoxamine, paroxetine (paxil) and sertraline (Zoloft).These class of drugs only inhibit the serotonin reuptake mechanism. Prozac was the first drug to be manufactured in this group, it has minimal side effects and has a long half due to its metabolite, and this makes it convenient as it can be used for once weekly dosing. Citalopram is the most selective of all. These drugs are preferred by most patients not because of their efficacy but due to their relatively low adverse effects (APA, 2008). Second generation and subsequent agents are a group of antidepressant introduced between 19 80 and 2005. Second generation antidepressants include amoxapine, maprotiline, tradozone and bupropion. Amoxapine and maprotiline bear close resemblance to tricyclics, while tradozone and bupropion are unique. Third generation drugs are newer and include drugs like venlafaxine, mirtazepine, nefazodone and duloxetine. Vast majority of drugs in this group individually bear multiple mode of action at the synaptic level with differing efficacy, however antagonism of serotonergic and noradrenergic pathways appears to be key in exerting their effects. Tradozone, nefazodone and mirtazepine will mainly inhibit serotonin uptake. Mirtazepine will stand out in its actions against noradrenergic receptors. Bupropion on the other side work via doperminergic pathways antagonism. Amoxapine has sedative, antimuscarinic and also antagonizes reuptake of dopamine. Maprotilne’s main mode of action will be through preventing noradrenaline uptake while venlafaxine has an additional serotonin uptake inhibition. Their side effects may include tardive dyskinesia, drug-induced Parkinsonism, akathisia and amenorrhea-galactorrhoea syndrome. A review by researchers in the University of North Carolina confirmed the use of second generation agents in the initial treatment and maintenance of major depressive disorder. Psychotherapy is recommended for non-severe depression in the 2011 APA guidelines. It’s especially used when there are coexisting social stressors such as inability to fit in school or at work or when patient has strained relations with parents, wife or peers. Problem solving therapy is used to help patient with day to day life decisions which may be difficult to those who are functionally impaired. Cognitive behavioral therapy is used in those patients who believe that they are worthless, its main purpose is to make sure patients look at themselves differently and even worthy. Psychotherapy can be used alone or in combination with pharmacotherapy. Current Electroconvulsive therapy is safer for use and has been approved by the FDA and the American psychiatric Association, APA for the treatment of major depressive disorder when antidepressants and therapy fail to work or when the depression has a psychotic phase. It’s also used for those who are suicidal and to those it had a positive outcome to it before The patient should be assessed after 8 weeks to antidepressant therapy and more than 8 weeks to psychotherapy to gauge whether there has been a response or a non response. When there is no response the 5 Ds should be checked. These are the diagnosis, dose, drug, duration of treatment and different treatment (DePaulo, 2008) .The diagnosis should be reassessed in that the disorder may have other features or it may not be it altogether, less than therapeutic levels for a patient makes the drug ineffective and shorter than the required duration makes the disorder resistant. Changing the drug to one in the same class or another is also recommended. To reduce the risk for relapse, the patient should be put on a continuous dose for a year and signs of relapse should be monitored. Patients who have had more than 3 major depressive disorders or are in constant contact with stressors should be put on maintenance dose. References Association, A. P. (2009). Practice guideline for major depressive disorder in adults. Michigan: the University of Michigan. Association, A. P. (2008). Treatment Works: Major Depressive Disorder : a Patient and Family Guide. Michigan: University of Michigan. J. Raymond DePaulo, J. J. (2008). Understanding Depression: What We Know and What You Can Do About it. New Jersey: John Wiley and Sons. William H. Reid, M. G. (2009). Dsm-Iv Training Guide. New York: Psychology Press. Read More