Antidepressants

Antidepressants alone are not enough

Prozac Capsules

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We should reconsider how we use antidepressants more effectively. The latest studies have shown that antidepressants restore the capacity of certain areas of the brain to repair abnormal neural pathways. According to neuroscientist Eero Castrén, the recipient of EUR 2.5 million of ERC funding, recovery requires redirection of these pathways through practice, rehabilitation or therapy.

This is a surprisingly blunt view, even for a respected neuroscientist such as Eero Castrén. After all, millions of people throughout the world have been prescribed antidepressants, and pharmaceutical companies have made a billion-dollar business out of selling them. Surely the system cannot be entirely wrong?

Recent studies suggest that this may be the case. Research on animal models demonstrates that antidepressants are not a cure as such. Rather, their role is to restore plasticity in the adult brain. Antidepressants reopen a window of brain plasticity, which allows the formation and adaptation of brain connections through the patient’s own activities and observations, similarly to a young child whose brain and experiences about the world develop in response to environmental stimuli.

Correcting abnormal pathways

When cerebral plasticity is reopened, problems caused by false connections in the brain can be addressed. Such problems can be manifested, for example, as phobias. Studies conducted on animal models by Professor Eero Castrén’s research group at the University of Helsinki show that therapy helps to reduce fears for a time, but an antidepressant alone provides no relief. By combining the two, however, long-term effects can be achieved.

“Simply taking drugs is not enough. We must also show the brain what the desired connections should be,” Professor Castrén of the Neuroscience Centre explains.

The need for both therapy and medical treatment may also explain why antidepressants sometimes seem to have no effect. If the patient’s environment and situation remain unchanged, the drug-induced capacity of the brain to change will not make the patient feel better.

Reaching this point is the result of years of research. Scientists discovered as early as the 1960s that antidepressants affect neurotransmitters in the brain, such as serotonin. Later, antidepressants were found to increase neurotrophins and their ability to transmit signals in the brain. Only recently have scientists begun to explore the effects of drugs on plasticity of brain networks.

Enhancing the plasticity of the adult human brain through antidepressants has opened a whole new field of research for Eero Castrén. He has received a five-year grant of EUR 2.5 million from the European Research Council (ERC) to investigate mechanisms related to adult brain plasticity.

http://www.ncbi.nlm.nih.gov/pubmed/22194582

Full bibliographic information
Fear erasure in mice requires synergy between antidepressant drugs and extinction training.Karpova NN, Pickenhagen A, Lindholm J, Tiraboschi E, Kulesskaya N, Agústsdóttir A, Antila H, Popova D, Akamine Y, Bahi A, Sullivan R, Hen R, Drew LJ, Castrén E.Science. 2011 Dec 23;334(6063):1731-4

Source: Helsingin yliopisto (University of Helsinki)

Prozac Capsules

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Americans are no strangers to antidepressants. During the last 20 years the use of antidepressants has grown significantly making them one of the most costly and the third most commonly prescribed class of medications in the U. S. According to the Centers for Disease Control and Prevention, from 2005-2008 nearly 8.9 percent of the U.S. population had at least one prescription in this drug class during any given month. A new study led by researchers at the Johns Hopkins Bloomberg School of Public Health examines national trends in antidepressant prescribing and finds much of this growth was driven by a substantial increase in antidepressant prescriptions by non-psychiatrist providers without any accompanying psychiatric diagnosis. The results are featured in the August 2011 issue of Health Affairs.

Over the past two decades, the use of antidepressant medications has grown to the point that they are now the third most commonly prescribed class of medications in the United States. Much of this growth has been driven by a substantial increase in antidepressant prescriptions by non-psychiatrist providers without an accompanying psychiatric diagnosis. The analysis found that between 1996 and 2007, the proportion of visits at which antidepressants were prescribed but no psychiatric diagnoses were noted increased from 59.5 percent to 72.7 percent. These results do not clearly indicate a rise in inappropriate antidepressant use, but they highlight the need to gain a deeper understanding of the factors driving this national trend and to develop effective policy responses. To the extent that antidepressants are being prescribed for uses not supported by clinical evidence, there may be a need to improve providers’ prescribing practices, revamp drug formularies, or vigorously pursue implementation of broad reforms of the health care system that will increase communication between primary care providers and mental health specialists.

Source: Johns Hopkins Bloomberg School of Public Health
Health Affairs

Anti-Depressants Raise Relapse Risk

Patients who use anti-depressants are much more likely to suffer relapses of major depression than those who use no medication at all, concludes a McMaster researcher.

In a paper that is likely to ignite new controversy in the hotly debated field of depression and medication, evolutionary psychologist Paul Andrews concludes that patients who have used anti-depressant medications can be nearly twice as susceptible to future episodes of major depression.

Andrews, an assistant professor in the Department of Psychology, Neuroscience & Behaviour, is the lead author of a new paper in the Journal Frontiers of Psychology.

The meta-analysis suggests that people who have not been taking any medication are at a 25 per cent risk of relapse, compared to 42 per cent or higher for those who have taken and gone off an anti-depressant.

Andrews and his colleagues studied dozens of previously published studies to compare outcomes for patients who used anti-depressants compared to those who used placebos.
They analyzed research on subjects who started on medications and were switched to placebos, subjects who were administered placebos throughout their treatment, and subjects who continued to take medication throughout their course of treatment.

Andrews says anti-depressants interfere with the brain’s natural self-regulation of serotonin and other neurotransmitters, and that the brain can overcorrect once medication is suspended, triggering new depression.

Though there are several forms of anti-depressants, all of them disturb the brain’s natural regulatory mechanisms, which he compares to putting a weight on a spring. The brain, like the spring, pushes back against the weight. Going off antidepressant drugs is like removing the weight from the spring, leaving the person at increased risk of depression when the brain, like the compressed spring, shoots out before retracting to its resting state.

“We found that the more these drugs affect serotonin and other neurotransmitters in your brain — and that’s what they’re supposed to do — the greater your risk of relapse once you stop taking them,” Andrews says. “All these drugs do reduce symptoms, probably to some degree, in the short-term. The trick is what happens in the long term. Our results suggest that when you try to go off the drugs, depression will bounce back. This can leave people stuck in a cycle where they need to keep taking anti-depressants to prevent a return of symptoms.”

Andrews believes depression may actually be a natural and beneficial — though painful
— state in which the brain is working to cope with stress. [continue reading…]

In Defense of Antidepressants

Peter D. Kramer clinical professor of psychiatry at Brown University opines in The New York Times in defense of Antidepressants .

In terms of perception, these are hard times for antidepressants. A number of articles have suggested that the drugs are no more effective than placebos.

Last month brought an especially high-profile debunking. In an essay in The New York Review of Books, Marcia Angell, former editor in chief of The New England Journal of Medicine, favorably entertained the premise that “psychoactive drugs are useless.” Earlier, a USA Today piece about a study done by the psychologist Robert DeRubeis had the headline, “Antidepressant lift may be all in your head,” and shortly after, a Newsweek cover piece discussed research by the psychologist Irving Kirsch arguing that the drugs were no more effective than a placebo.

Could this be true? Could drugs that are ingested by one in 10 Americans each year, drugs that have changed the way that mental illness is treated, really be a hoax, a mistake or a concept gone wrong? link to continue reading the article

Source: New York Times