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Psychopharmacology

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Psychopharmacology is the study of the effects of any psychoactive drug that acts upon the mind by affecting brain chemistry. Fly agaric can be regarded as the first such drug, being known from at least 10,000 BCE.

Generally hallucinogenic drugs were used in hunter-gatherer societies, which use can still be observed today. With the dawn of the Neolithic, drugs which require a longer time for production followed, mainly narcotic drugs such as alcohol and opium, but also cannabis.

However, the use of psychiatric drugs to restore mental health, or at least limit aberrant behaviour, has only been widespread since the 1950s when a number of new classes of drugs were discovered, notably tranquillizers and antidepressants.

Following their discovery some of these drugs gained popularity among psychiatrists and general practitioners. Some once-popular drugs are now out of favor, and there are fashions in psychiatric drugs, as with any other kind of drug.

Reduction of anxiety

Barbiturates were used as hypnotics and as anxiolytics, but the development of the safer benzodiazepines (Lowell Randall and Leo Sternbach, 1957) in the 1960s and 1970s led to billions of doses being consumed annually under tradenames like Mogadon, Valium (diazepam, 1963) or Librium (chlordiazepoxide). However, the problems of chronic use and dependence led to the development of other drugs, such as the azapirones.

Antipsychotic drugs

Outside of the more popular drugs there was success in the treatment of some of the symptoms of psychosis and depression. The first antipsychotic compound, for the treatment of the symptoms of schizophrenia, was chlorpromazine (known by tradenames like Largactil or Thorazine) in 1953. It went beyond simple sedation, with patients showing improvements in thinking and emotional behaviour, and over 100 million patients were treated. From chlopromazine a number of other similar antidopaminergic compounds were developed, such as the phenothiazines. Such drugs had a revolutionary role in transforming mental institutions from an almost purely custodial role. But the limited knowledge of brain chemistry means that even more modern compounds cause a range of extrapyramidal side-effects and while effective at controlling acute symptoms are of less value in treating chronic symptoms. Enthusiasm for the first generation of anti-psychotic medications peaked in the late 1960s, but the image of the drugs plummeted in the mid-1970s, as studies emerged showing high rates of tardive dyskinesia, a typically permanent neurological disorder involving involuntary movements, in chronic users. The first generation of antipsychotic drugs are now commonly referred to as typical antipsychotics.

In the 1990s, several atypical antipsychotic drugs were first marketed. Atypical antipsychotics are believed to have a lower incidence of tardive dyskinesia and extrapyramidal side-effects than the first generation typical antipsychotics. The atypical antipsychotics are believed to be better at treating the "negative symptoms" of schizophrenia.

LSD

LSD was promoted in the 1950s as a psychiatric cure-all, useful for treating schizophrenia, criminal behavior, sexual deviancy, alcoholism, and a wide variety of other mental ailments. Drug manufacturer Sandoz Laboratories suggested in its literature that psychiatrists take LSD themselves, to gain a better subjective understanding of the schizophrenic experience. Many users have reported profound, life-transforming experiences as a result of taking LSD, while others have experienced intensely negative "bad trips", and a few have devolved into states of LSD psychosis. While scientific research into the effects and potential uses of LSD was common in the 1950s, it gradually declined as LSD became increasingly associated with spiritual experiences, recreational use, and hippies in the 1960s.

LSD was also central to experiments conducted as part of the CIA's MKULTRA program, which was focused on finding reproduceable methods to program and control human minds. Subjects included military personnel and private citizens, the vast majority of whom had no knowledge of the nature of the experimentation prior to their participation. Most of the experiments constituted significant breaches of human rights, and have since been openly denounced by the United States Government. LSD itself proved ineffective as a means of controlling subjects, but reports indicate that many of the people involved suffered significant psychological trauma as a result.

Several researchers, most prominently erstwhile Harvard professor Dr. Timothy Leary, dissociated themselves from the mainstream mental health research establishment as its support for LSD research declined and transitioned to roles as spiritual gurus, advocating the use of LSD for personal spiritual growth. LSD was prohibited in the United States in 1967, and systematic research since that time has been uncommon.

MDMA

MDMA, commonly known as Ecstasy, was popularized as an adjucant to talk therapy in the 1960s and 1970s by Dr. Alexander Shulgin. One primary effect of Ecstasy is diminution of inhibitions, rendering users extremely comfortable talking about themselves and others.

Potential theraputic uses of MDMA have been overshadowed by its popularity as a recreational drug and negative public perceptions fostered by anti-drug groups. Limited research continues, with University of Manchester researchers determining that MDMA dramatically reduces tremors in patients receiving L-DOPA treatment for Parkinson's Disease. Other researchers have implicated long-term MDMA use as a potential cause of Parkinson's Disease.

Much remains unknown about the potential uses and effects of MDMA. The United States DEA's scheduling of MDMA as a Schedule 1 drug with no legitimate medical uses has severely hampered research, while some experts have recommended it be listed instead on Schedule 3, a less severe classification which would indicate the possibility of medical applications.

Antidepressant drugs

Two major classes of drugs combatting depression were developed in the late 1950s, one group based on iproniazid, an MAOI developed at Hoffmann-La Roche in 1956, the other on imipramine, a tricyclic antidepressant developed by R. Kuhn at Geigy Laboratories in 1958. Improvements were made but the results were less marked than with anti-psychotic drugs. This category also includes tetracyclic antidepressants or SSRIs such as Prozac, discovered by D. T. Wong at Eli Lilly and Company in 1974 and approved by the FDA in 1987).

Mood stabilizers

In 1949, the Australian John Cade discovered that lithium salts could control mania, reducing the frequency and severity of manic episodes. It did not take long for others to discover that these drugs also reduced the frequency and severity of depressive episodes. Other mood stabilizers include valproic acid, carbamazepine, lamotrigine, and topiramate.

Treatment of addiction

Research with the drug ibogaine to treat heroin addiction has shown much promise in eliminating physical withdrawal symptoms. The drug is obtained from an African plant and was used as early as the 1960s by Claudio Naranjo.