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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 10000 BCE.
Generally hallucinogenic drugs were used in
hunter-gatherer societies, which 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 amongst 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 and hippies in the 1960s.
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 fed by anti-drug group propaganda. 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 (despite many expert recommendations that MDMA be Schedue 3, for drugs with potential medical
applications) has severely hampered research.
Antidepressant drugs
For depression two major classes of drugs were developed
in the late 1950s, one group based on iproniazid (an MAOI developed at Hoffman-LaRoche,
1956) the other on imipramine (a tricyclic
antidepressant developed by R. Kuhn at Geigy Labs in 1958). Improvements were effected 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 labs in 1974, FDA approved 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.
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