Medications antidepressants

The market for antidepressant medication is very large. The market in the United States is - 6 x 10 per year. 

Each antidepressant has a response rate of approximately 60% to 80%, and no antidepressant medication or class has been reliably shown to be more efficacious than another. 

Owing to increased awareness of the illness and the advent of newer and safer antidepressant medications, the past two decades have seen improvements in the screening, diagnosis, and treatment of MDD. The willingness of generalist practitioners to involve themselves in the identification and treatment of MDD is noteworthy. To that end, antidepressants have become some of the most commonly prescribed drugs, and they account for 10 of the top 100 prescription drugs dispensed in the United States.1 Despite recent increases in the treatment of MDD, inadequate treatment remains a serious concern.2... 

Given that there are now about 25 antidepressant medications, one apparent clinical perplexity is for the clinician to distinguish the various agents. But each antidepressant has its unique blend of characteristics, and in fact, even individual drugs within the same class have important differences.22... 

Each antidepressant has a response rate of approximately 60% to 80%, and no antidepressant medication or class has been reliably shown to be more efficacious than another 22 MAOIs may be the most effective therapy for atypical depression, but MAOI use continues to wane because of problematic adverse effects, dietary restrictions, and possibility of fatal drug interactions.22,28 There is some evidence that dual-action antidepressants, such as TCAs and SNRIs, may be more effective for inpatients with severe depression than are the single-action drugs such as SSRIs,22,28 but the more general assertion that multiple mechanisms of action confer efficacy advantages is quite controversial.33... 

Approximately one-third of patients with MDD do not respond satisfactorily to their first antidepressant medication.37 In such cases, the clinician must evaluate the adequacy of antidepressant therapy, including dosage, duration, and patient compliance.17 Treatment reappraisal also should include verification of the patient s diagnosis and reconsideration of clinical factors that could be impeding successful therapy, such as concurrent medical conditions (e.g., thyroid disorder), comorbid psychiatric conditions (e.g., alcohol abuse), and psychosocial issues (e.g., marital stress).16... 

Antidepressant medications appear to be useful for certain children and adolescents, particularly those who have severe or psychotic depression, fail psychotherapeutic measures, or experience chronic or recurrent depression. SSRIs generally are considered the initial antidepressants of choice, although comorbid conditions may favor alternative agents. Clinicians should be aware of the possibility of behavioral activation with the SSRIs, including such symptoms as impulsivity, silliness, daring conduct, and agitation.44 Desipramine should be used with caution in this population because of several reports of sudden death, and a baseline and follow-up electrocardiogram (ECG) may be warranted when this medication is used to treat pediatric patients.9... 

The FDA is in the process of analyzing data to determine whether there is an increased risk of suicidality in adult patients similar to that seen in pediatric patients (see above). Even though the suicidality risk for adults taking antidepressant medications... 

The clinician should bear in mind the toxic potential for the various antidepressant medications when patients already have or develop suicidality. The TCAs and MAOIs have narrow therapeutic indices, whereas the SSRIs, SNRIs, nefa-zodone, and mirtazapine have wide therapeutic indices.22... 

SSRIs are theorized to reduce the frequency of hot flashes by increasing serotonin in the central nervous system and by decreasing LH. Of the SSRIs, citalopram, paroxetine, and sertraline all have been studied and have demonstrated a reduction in hot flashes while treating other symptomatic complaints such as depression and anxiety.33 Venlafaxine, which blocks the reuptake of serotonin and norepinephrine, has demonstrated a reduction in hot flashes primarily in the oncology population.34 Overall, these antidepressant medications offer a reasonable option for women who are unwilling or cannot take hormonal therapies, particularly those who suffer from depression or anxiety. These agents should be prescribed at the lowest effective dose to treat symptoms and may be titrated based on individual response. 

Research in psychopharmacology has shown that ethnicity must be considered in psychiatry as well (Lawson, 1986 Pi 8c Simpson, 2005). Early clinical trials with antipsychotic and antidepressant medications showed that ethnic minorities may respond when given the same doses as Caucasians, and may have more side effects (Lawson, 1986 Lawson, 1990). However, dosing cannot be used as a measure of appropriate pharmacotherapy because an extensive literature has shown that African Americans often receive higher doses of antipsychotics despite evidence of more side effects. 

Why are side effects important Imagine that you have been recruited for a clinical trial of an antidepressant medication. As part of the required informed-consent procedure, you are told that you may be given a placebo instead of the active medication, but because this is a double-blind trial, you will not be told which you are getting until the study is over. You are told that... 

In this chapter we have looked at the results of published clinical trials of antidepressant medication. The published studies showed a significant, but surprisingly small, effect of antidepressants over placebos. But as I noted at the beginning of the chapter, those data represented only the beginning. As I later discovered, there were also studies that had been withheld from publication. These unpublished studies were clinical trials that did not show a significant benefit for drugs over placebo medication - trials that the drug companies withheld... 

The article that follows is a controversial one. It reaches a controversial conclusion - that much of the therapeutic benefit of antidepressant medications actually derives from placebo responding. The article reaches this conclusion by utilizing a controversial statistical approach - meta-analysis. And it employs meta-analysis controversially - by meta-analysing studies that are very heterogeneous in subject selection criteria, treatments employed, and statistical methods used. Nonetheless, we have chosen to publish the article. We have done so because a number of the colleagues who originally reviewed the manuscript believed it had considerable merit, even while they recognized the clearly contentious conclusions it... 

Our first published report of the FDA data was accompanied by nine expert commentaries, some of them by researchers who had conducted clinical trials of antidepressant medication. Although there were vast differences in interpretation, this time there were no doubts about the accuracy of our analysis. Some commentators argued that our analysis had actually overestimated the real effect of antidepressants. Others argued that the clinical trials sponsored by the drug industry are flawed and that they may underestimate the actual benefit of antidepressants. But all... 

The point is that the practice of medicine should be based on empirical evidence, not on its absence. I do not have to prove that antidepressants do not work. Instead, it is the job of the drug companies to prove that they do work. If the trials were flawed, then clinically significant differences between antidepressant and placebo have not been established for most patients. If the trials were not flawed, the data indicate that clinically significant differences between antidepressant and placebo have not been established for most patients (quoted from the previous sentence). Either way, the objective of proving the effectiveness of antidepressant medication has not been met. 

Depression, we are told over and over again, is a brain disease, a chemical imbalance that can be adjusted by antidepressant medication. In an informational brochure issued to inform the public about depression, the US National Institute for Mental Health tells people that depressive illnesses are disorders of the brain and adds that important neurotransmitters - chemicals that brain cells use to communicate - appear to be out of balance . This view is so widespread that it was even proffered by the editors of PLoS [Public Library of Science] Medicine in their summary that accompanied our article. Depression, they wrote, is a serious medical illness caused by imbalances in the brain chemicals that regulate mood , and they went on to say that antidepressants are supposed to work by correcting these imbalances. 

When Schildkraut introduced the monoamine theory of depression, he admitted that there was little direct evidence for it. Instead, it was based on the supposed effectiveness of antidepressant medication and the mistaken belief that reserpine makes people depressed. Schildkraut acknowledged that Most of this evidence is indirect, deriving from pharmacological studies with drugs such as reserpine, amphetamine and the monoamine oxidase inhibitor antidepressants which produce affective changes. 21 A half-century has passed since his chemical-imbalance theory of depression was introduced, and the presumed effectiveness of antidepressants remains the primary evidence in its support. But as we have seen, the therapeutic effects of antidepressants are largely due to the placebo effect, and this pretty much knocks the legs out from under the biochemical theory. 

There is only one group of research subjects in whom rapid depletion of serotonin sometimes produces clinical depression. These are depressed patients in remission who are currently taking SSRIs. About half of these patients relapse when serotonin is depleted. Note that this only happens if they are still taking antidepressant medication. If they have stopped medication, depleting... 

The reason for this warning is that abrupt cessation of SSRIs produces withdrawal symptoms in about 20 per cent of patients. Symptoms of withdrawal from antidepressant medication include gastrointestinal disturbances (abdominal cramping and pain, diarrhoea, nausea and vomiting), flu-like symptoms, headaches, sleep disturbances, dizziness, blurred vision, numbness, electric-shock sensations, twitches and tremors. Abrupt withdrawal can also produce symptoms of depression and anxiety, which can occur within hours of the first missed dose of the drug.11 Withdrawal symptoms are sometimes mistaken for a relapse, leading patients to resume antidepressant medication and to conclude that they need it in order to remain free of depression. Technically, this is not considered addiction , but it does seem awfully close. 

Of all the alternatives to antidepressant medication, psychotherapy is the most thoroughly researched. It has been the subject of... 

The central theme of this book is that much - if not all - of the therapeutic effects of antidepressants are due to the placebo effect. Might this not also be true of the effect of psychotherapy on depression Could this also be a placebo effect This is one of the objections that I hear quite often when I am invited to speak about my research. Psychotherapy is no more effective than antidepressant medication, these critics contend. So if antidepressants are merely placebos, so too is psychotherapy. 

There seems to be considerable reluctance in some parts of the medical community to acknowledge the benefits of exercise in the treatment of depression. One meta-analysis of clinical trials showed that physical exercise was as effective as psychotherapy or antidepressant medication and much better than no treatment. But the authors concluded that the effectiveness of exercise in reducing symptoms of depression cannot be determined ,45 and the editors of the journal introduced the article with an editorial comment entitled effectiveness of exercise in managing depression is not shown by meta-analysis .46 Why not Because there were flaws in the way many of the studies had been designed. To be fair, there were indeed shortcomings in the studies, but these shortcomings also characterize clinical trials of antidepressants.47 If clinical trials like these do not establish the effectiveness of physical exercise as a treatment for depression, neither do they establish the effectiveness of antidepressants. 

Ferguson, James M., SSRI Antidepressant Medications Adverse Effects and Tolerability , The Primary Care Companion to The Journal of Clinical Psychiatry 3, no. 1 (2001) 22-27... 

Emperor s New Drugs An Analysis of Antidepressant Medication Data Submitted to the U.S. Food and Drag Administration , Prevention Treatment, no. 23 (2002a) http //www.joumals.apa.org/preven-tion/volume5/pre0050023a.html... 

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