Antipsychotic Medication

Antipsychotic medications are a class of psychiatric drugs developed primarily to reduce the acute symptoms of psychosis — hallucinations, delusions, disorganized thought, and agitation — in conditions including schizophrenia, mania, and schizoaffective disorder. The class divides broadly into first-generation agents (called “typical” antipsychotics or neuroleptics, introduced in the 1950s) and second-generation agents (called “atypical” antipsychotics, introduced from the early 1990s onward). Both generations primarily work by blocking dopamine D2 receptors. Their short-term efficacy in reducing acute psychotic symptoms is supported by clinical trial evidence, though journalist Robert Whitaker’s Anatomy of an Epidemic (2010) documents that this evidence base is more limited than commonly presented. Their long-term outcomes record — accumulated over fifty years of naturalistic research, NIMH-funded longitudinal studies, and WHO cross-cultural investigations — is substantially more contested than the short-term record, and is the primary focus of this page.

Discovery and Early History

Chlorpromazine, the first antipsychotic drug (initially sold as Thorazine in the United States), was discovered through post-WWII malaria research rather than through any understanding of psychotic illness. The French surgeon Henri Laborit was using chlorpromazine as a presurgical sedative and in December 1951 reported at an anesthesiology conference in Brussels that it produced a “veritable medicinal lobotomy” — inducing indifference, slowed response, and emotional neutrality without loss of consciousness.(Whitaker, Robert, 2010) French psychiatrists Jean Delay and Pierre Deniker administered it to psychotic patients beginning in 1952. Deniker coined the term “neuroleptic” — meaning “that which takes hold of the nervous system” — and explicitly warned that the drug could induce parkinsonian symptoms and possibly “true encephalitis epidemics.” A U.S. psychiatrist present at a 1955 Philadelphia conference stated clearly: “We are not treating diseases with this drug. We are using a neuropharmacologic agent to produce a specific effect.”(Whitaker, Robert, 2010)

Smith Kline and French secured FDA approval for Thorazine on March 26, 1954.(Whitaker, Robert, 2010) Despite having tested the drug on fewer than 150 psychiatric patients prior to the FDA application, the company’s president publicly claimed the drug had undergone “the most rigorous testing imaginable” with “well over five thousand animals.”(Whitaker, Robert, 2010)

In 1963, the NIMH conducted a six-week randomized trial of Thorazine and other neuroleptics against placebo. The drugs were found more effective than placebo at reducing acute psychotic symptoms, and the researchers concluded they should be regarded as “antischizophrenic in the broad sense.” With this trial, the nomenclature shifted: “major tranquilizers” became “antipsychotic medications,” implying a disease-specific mechanism before any such mechanism had been identified.(Whitaker, Robert, 2010) The transformation was complete by the late 1950s and early 1960s: drugs originally described as agents producing emotional indifference were relabeled as targeted treatments for brain diseases.(Whitaker, Robert, 2010)

The Dopamine Hypothesis

By 1970, Whitaker argues, psychiatry faced two possible accounts of what it had done. Either it had discovered drugs that corrected genuine chemical imbalances in mentally ill brains, or it had turned agents that perturb normal brain function into “magic bullets” to claim medical legitimacy; if the second possibility were true, “it stands to reason that the long-term outcomes produced by the drugs might be problematic in kind.”(Whitaker, Robert, 2010)

The scientific rationale for antipsychotics developed after the drugs were already in wide use — constructed retrospectively from their observed effects. The foundational story runs as follows. In the 1950s, researchers including Arvid Carlsson noted that reserpine (a drug that depleted brain monoamines) made animals lethargic and appeared to produce a depressive-like state. This suggested that low monoamines caused depression, and by parallel logic, that drugs like imipramine worked by raising them.(Whitaker, Robert, 2010) Joseph Schildkraut’s 1965 paper in the Archives of General Psychiatry formalizing the “catecholamine hypothesis” of affective disorders was the first explicit pillar of biological psychiatry — though Schildkraut himself acknowledged the hypothesis was “at best a reductionistic oversimplification of a very complex biological state.”(Whitaker, Robert, 2010)

Beginning in 1969, Malcolm Bowers at Yale measured serotonin metabolites (5-HIAA) in the cerebrospinal fluid of depressed patients and found them lower than normal, though the difference was not statistically reliable.(Whitaker, Robert, 2010) His 1974 follow-up, with more carefully selected patients who had not previously taken antidepressants, found that unmedicated depressed patients had perfectly normal 5-HIAA levels.(Whitaker, Robert, 2010)

The dopamine hypothesis of schizophrenia was constructed from two separate observations. First, antipsychotics reliably induced Parkinsonian symptoms; since Parkinson’s disease was known to result from destruction of dopaminergic neurons in the basal ganglia, researchers inferred that antipsychotics worked by blocking dopamine. Second, amphetamines — which trigger hallucinations and paranoid delusions — were found to elevate dopamine activity. The logical inference: if too much dopamine causes psychosis, and antipsychotics block dopamine, then schizophrenia must involve dopamine excess. Dutch scientist Jacques Van Rossum made this explicit with the dopamine hypothesis of schizophrenia in the 1960s.(Whitaker, Robert, 2010) The human brain, with its 100 billion neurons and perhaps 150 trillion synapses, was in this framework characterized by a single simple disorder of overactive dopaminergic pathways.(Whitaker, Robert, 2010)

The hypothesis generated fifteen years of research measuring dopamine metabolites (HVA) in the cerebrospinal fluid of schizophrenic patients. The results were not confirmatory. Multiple independent studies from 1975 onward found that unmedicated schizophrenic patients had normal dopamine metabolite levels — not elevated ones.(Whitaker, Robert, 2010) When elevated D2 receptor density was found in schizophrenic brains at autopsy (Seeman 1978), the finding was subsequently shown to be iatrogenic: it was caused by long-term neuroleptic use, not by the disease itself. British investigators confirmed that the D2 increase was “seen only in patients in whom neuroleptic medication had been maintained until the time of death, indicating that they were entirely iatrogenic.”(Whitaker, Robert, 2010)

By 1990, Pierre Deniker himself — one of the original champions of chlorpromazine — stated that “the dopaminergic theory of schizophrenia retains little credibility for psychiatrists.” NIMH director John Kane echoed the view in 1994: there was “no good evidence for any perturbation of the dopamine function in schizophrenia.” Kenneth Kendler’s 2005 summary was definitive: “We have hunted for big simple neurochemical explanations for psychiatric disorders and have not found them.”(Whitaker, Robert, 2010)(Whitaker, Robert, 2010) Despite this, the public continued to be told that schizophrenia involved “too much dopamine” and that antipsychotics worked like “insulin for diabetes.”

Whitaker traces this gap between the science and the public narrative to a storytelling formula adopted by pharmaceutical companies. When ADHD was diagnosed in children and Ritalin was found to increase dopamine release, parents were told their children suffered from low dopamine. Whitaker’s explanation: “the only reason they were told that was because Ritalin stirred neurons to release extra dopamine.” The mechanism of the drug’s action was inverted and presented as the disease’s cause. This formula was applied to every subsequent drug class: identify the drug’s mechanism, then tell the public that patients suffer from the opposite deficit or excess.(Whitaker, Robert, 2010) Robert Whitaker further argues that the chemical-imbalance theory was embraced by psychiatry not because evidence confirmed it, but because it allowed psychiatrists to adopt the identity of “real doctors” prescribing anti-disease pills comparable to antibiotics.(Whitaker, Robert, 2010)

Mechanism: Neuroadaptation, Not Correction

The actual mechanism of antipsychotic drugs — as established by their own discoverers’ early descriptions, later neuroscience, and a landmark 1996 paper by NIMH director Steve Hyman — is not the correction of a pre-existing chemical imbalance but the creation of a new one. Thorazine and other first-generation antipsychotics block 70 to 90 percent of all D2 receptors in the brain. In response, presynaptic neurons begin pumping out more dopamine and postsynaptic neurons increase D2 receptor density by 30 percent or more — a compensatory upregulation. After about three weeks, the pathway’s feedback mechanism begins to fail, and presynaptic neurons fire in irregular patterns or turn quiescent. It is this “inactivation” of dopaminergic pathways — described by the APA’s own Textbook of Psychopharmacology as the probable basis for antipsychotic action — that reduces psychotic symptoms.(Whitaker, Robert, 2010)

Hyman’s 1996 paper “Initiation and Adaptation” established that all psychotropic drugs create “perturbations in neurotransmitter functions” that trigger homeostatic brain adaptations, and that after chronic administration they produce “substantial and long-lasting alterations in neural function” leaving the brain in a “qualitatively as well as quantitatively different” state from normal.(Whitaker, Robert, 2010) The implication, which Whitaker draws out explicitly, is that prior to drug treatment, patients diagnosed with schizophrenia do not suffer from any known chemical imbalance — it is the medication that creates the abnormal brain state.(Whitaker, Robert, 2010) Whitaker concludes from this that psychiatry’s original description of its drugs as agents that perturb normal brain function was “the scientifically accurate one,” and that the subsequent reconception of them as targeted correctives for chemical imbalances “arose as much from wishful thinking as from science” and was not validated by research.(Whitaker, Robert, 2010)

Short-Term Efficacy

The 1961 NIMH nine-hospital trial remains the foundation of the antipsychotic evidence base: 75 percent of neuroleptic-treated patients were rated “much improved” versus 23 percent on placebo after six weeks.(Whitaker, Robert, 2010) A 1995 review by Patricia Gilbert of 66 relapse studies involving 4,365 patients found that 53 percent of drug-withdrawn patients relapsed within ten months versus 16 percent of those maintained on antipsychotics.(Whitaker, Robert, 2010)

A 2007 Cochrane Collaboration meta-analysis of 50 chlorpromazine-versus-placebo studies found the advantage of drug over placebo smaller than commonly believed, calculating that “seven patients had to be treated with chlorpromazine to produce a net gain of one ‘global improvement’” and describing the evidence as “surprisingly weak.”(Whitaker, Robert, 2010) As of 2002, after fifty years of neuroleptic use, researchers at the University of Maryland acknowledged that “well-designed long-term studies are virtually nonexistent,” and a European Psychiatry editorial asked: “Are neuroleptics effective in treating schizophrenia? There is no compelling evidence on the matter, when ‘long-term’ is considered.”(Whitaker, Robert, 2010)

The relapse studies that support long-term maintenance treatment have a methodological vulnerability. Adele Viguera at Harvard Medical School reanalyzed the same 66 relapse studies and found that when drugs were gradually (rather than abruptly) withdrawn, the relapse rate was only one-third as high — similar to the relapse rate of drug-maintained patients. The standard designs used abrupt withdrawal, dramatically inflating the apparent risk of discontinuation.(Whitaker, Robert, 2010)

Long-Term Outcomes

The long-term naturalistic and longitudinal record tells a more complex story than short-term trial data.

In the pre-Thorazine window (1946–1954), 62 to 85 percent of first-episode schizophrenia patients were discharged within 12 to 18 months, and 70 percent were living successfully in the community five years later — without antipsychotic drugs or federal disability programs.(Whitaker, Robert, 2010) A 1961 California Department of Mental Hygiene study of 1,413 first-episode patients found that 88 percent of those not prescribed a neuroleptic were discharged within 18 months, versus 74 percent of those treated with drugs — leading investigators to conclude that “drug-treated patients tend to have longer periods of hospitalization.”(Whitaker, Robert, 2010)

The NIMH’s own follow-up of its 1961 nine-hospital trial produced a startling result: patients who had received placebo in the initial trial had lower rehospitalization rates after one year than those who received any of the three active phenothiazines, with relapse rates rising in direct correlation with drug dosage.(Whitaker, Robert, 2010) A 1975 study by Bockoven and Solomon compared 1947 patients (treated without neuroleptics) to 1967 patients (treated with neuroleptics) and found that 45 percent of the earlier cohort had no relapse in five years and 76 percent were living successfully in the community, versus only 31 percent relapse-free at five years among the later cohort, who were also much more “socially dependent.” The investigators concluded that extended neuroleptic use in aftercare “may prolong the social dependency of many discharged patients.”(Whitaker, Robert, 2010)

Three NIMH-funded studies in the 1970s — by Carpenter and McGlashan, Rappaport, and Loren Mosher’s Soteria Project — each found that schizophrenia patients treated without antipsychotics had better long-term outcomes. Rappaport’s study found that among 24 patients never exposed to antipsychotics, only two relapsed over three years — by far the best outcomes of any group.(Whitaker, Robert, 2010)

The most comprehensive longitudinal study is Martin Harrow’s NIMH-funded 15-year prospective study of schizophrenia outcomes, published in 2007. At the 15-year follow-up, 40 percent of patients who had discontinued antipsychotics were in recovery, more than half were working, and fewer than 30 percent suffered from psychotic symptoms. Among those continuously on antipsychotics, only 5 percent were in recovery and 64 percent were actively psychotic — one-eighth the recovery rate and a threefold higher rate of uniformly poor outcomes.(Whitaker, Robert, 2010)(Whitaker, Robert, 2010) Harrow told the APA: “I conclude that patients with schizophrenia not on antipsychotic medication for a long period of time have significantly better global functioning than those on antipsychotics.”

The WHO’s two cross-cultural schizophrenia studies found that patients in developing countries had substantially better outcomes than in developed countries.(Whitaker, Robert, 2010) In the second study, only 16 percent of poor-country patients were regularly maintained on antipsychotics versus 61 percent in rich countries.(Whitaker, Robert, 2010) Medication use was highest in Moscow, which had the highest percentage of chronically ill patients.(Whitaker, Robert, 2010) Courtenay Harding’s Vermont longitudinal study found that 34 percent of previously “hopeless” chronic schizophrenia patients had fully recovered twenty years later; she reported that all of them “had long since stopped taking medications.”(Whitaker, Robert, 2010)

Mechanism of Long-Term Harm: Supersensitivity Psychosis

Guy Chouinard and Barry Jones at McGill proposed in the late 1970s that long-term neuroleptic use causes dopamine receptor supersensitivity — a compensatory upregulation of D2 receptors that makes the dopaminergic system more reactive. Upon withdrawal, this supersensitivity may trigger a psychotic episode more severe than the original illness. Chouinard and Jones called this “supersensitivity psychosis” and proposed that the need for continued neuroleptic treatment “may itself be drug-induced.”(Whitaker, Robert, 2010) Their 1982 follow-up found that 30 percent of 216 schizophrenia outpatients showed signs of tardive psychosis, occurring at roughly 3 percent per year — meaning approximately 45 percent might be affected after 15 years.(Whitaker, Robert, 2010) Philip Seeman’s animal studies confirmed that D2 receptor upregulation from neuroleptics could become irreversible, requiring two months of abstinence for each month of exposure — and eventually becoming permanent.(Whitaker, Robert, 2010)

This mechanism explains the apparent paradox in the relapse literature: because antipsychotics sensitize the dopaminergic system, withdrawal triggers a rebound psychosis that looks like relapse but may in part be a pharmacological effect rather than the natural course of illness. A 2005 study by Seeman found that all known psychosis-inducing triggers — amphetamines, phencyclidine (PCP), hippocampal lesions, gene knockouts — increase high-affinity D2 receptors in the brain; antipsychotics, including atypicals, double the density of the same receptors.(Whitaker, Robert, 2010)

Physical Harm: Tardive Dyskinesia and Early Death

By the 1970s, antipsychotics were known to cause tardive dyskinesia (TD) — a permanent gross motor dysfunction that persists even after drug withdrawal, evidence of irreversible neurological damage. They also caused emotional “zombie” states, Parkinsonian symptoms, akathisia (a restless motor agitation linked to suicide and violence), impaired learning, and chronic social disengagement. Jonathan Cole’s 1977 article “Is the Cure Worse Than the Disease?” noted that studies showed at least 50 percent of schizophrenia patients could fare well without antipsychotics and recommended that “every schizophrenic outpatient maintained on antipsychotic medication should have the benefit of an adequate trial without drugs.”(Whitaker, Robert, 2010)(Whitaker, Robert, 2010)

MRI studies from 1994 to 1998 found that antipsychotics caused dose-related swelling of basal ganglia and thalamus and shrinkage of frontal lobes. Nancy Andreasen conceded in a 2008 New York Times interview: “The more drugs you’ve been given, the more brain tissue you lose. They block basal ganglia activity. The prefrontal cortex doesn’t get the input it needs and is being shut down by drugs. That reduces the psychotic symptoms. It also causes the prefrontal cortex to slowly atrophy.”(Whitaker, Robert, 2010)

By the early 2000s, people with serious mental illness in the United States were dying on average 25 years earlier than the general population.(Whitaker, Robert, 2010) This premature mortality was largely attributed to the metabolic and cardiovascular effects of antipsychotic and mood-stabilizing medications.(Whitaker, Robert, 2010)

Second-Generation Atypicals and the CATIE Trial

Clozapine, the first atypical antipsychotic, had been available since the 1970s but withdrawn in many markets after deaths from agranulocytosis (immune cell depletion). It was reintroduced in the United States in 1989 with mandatory blood monitoring and positioned as a drug for treatment-resistant schizophrenia. Risperidone (Risperdal, Janssen) received FDA approval in 1993, followed by olanzapine (Zyprexa, Eli Lilly) in 1996. The marketing narrative for these “atypicals” was that they acted on both dopamine and serotonin, had fewer extrapyramidal side effects than first-generation drugs, and represented a genuine clinical advance.

Janssen designed its risperidone approval trials by comparing multiple doses of risperidone to a high dose of haloperidol (Haldol) — ensuring at least one risperidone dose would appear safer by comparison. The FDA told Janssen directly in its approval letter that it would consider any advertisement claiming risperidone superior to haloperidol to be “false, misleading, or lacking fair balance.”(Whitaker, Robert, 2010) Eli Lilly’s pivotal olanzapine trials were similarly designed against high-dose haloperidol. During the trials, 20 patients died, 22 percent suffered serious adverse events, and two-thirds failed to complete the studies. FDA reviewer Paul Leber warned that “no one should be surprised if, upon marketing, events of all kinds and severity not previously identified are reported.”(Whitaker, Robert, 2010)

The atypical narrative was effectively demolished by the NIMH’s 2005 CATIE (Clinical Antipsychotic Trials of Intervention Effectiveness) Trial — the most rigorous real-world comparison ever conducted. Involving 1,432 patients over 18 months, CATIE found no significant differences between atypical and first-generation antipsychotics. More striking, 74 percent of patients were unable to remain on their assigned medication, mostly because of “inefficacy or intolerable side effects.”(Whitaker, Robert, 2010) Two prominent psychiatrists wrote in the Lancet that the atypical antipsychotic story “can now be regarded as invention only,” a tale “concocted by the drug industry for marketing purposes and only now being exposed.”(Whitaker, Robert, 2010) Eli Lilly settled litigation over Zyprexa’s metabolic risks — diabetes, dramatic weight gain — for $1.4 billion in 2009; internal documents obtained through Alaskan legal proceedings showed Lilly had known about and concealed these risks for years.(Whitaker, Robert, 2010) The Alaska proceedings had broader legal significance: in 2006 the Alaska Supreme Court ruled in Myers v. Alaska Psychiatric Institute that antipsychotic medications can cause “profound and lasting negative effects on the brain” and that forced medication requires “clear and convincing evidence” that benefits outweigh those risks — a judicial acknowledgment of long-term antipsychotic harms that set a precedent for patients’ rights in forced-treatment cases.(Whitaker, Robert, 2010)

Evidence Suppression and Institutional Dynamics

Whitaker argues that the accumulated evidence forms a coherent chain: from Cole, Bockoven, Rappaport, Carpenter, Mosher, Harding, the WHO, and Harrow, a consistent line of findings points toward antipsychotics worsening long-term schizophrenia outcomes, with Chouinard and Jones supplying the biological mechanism.(Whitaker, Robert, 2010) The population-level consequence, Whitaker argues, is visible in disability statistics: since the arrival of Thorazine the disability rate due to psychotic illness has increased fourfold, from 1 in 617 Americans in 1955 to approximately 1 in 125 Americans on SSI/SSDI for schizophrenia or related psychotic disorders by 2007.(Whitaker, Robert, 2010)

The discrepancy between the short-term trial literature and the long-term naturalistic record has not been a failure of science to produce evidence; it has been a failure to disseminate and respond to evidence that contradicts the dominant treatment paradigm. The NIMH issued 89 press releases in 2007 touting psychiatric drug benefits and issued none on Harrow’s landmark 15-year study.(Whitaker, Robert, 2010) The APA’s 2004 schizophrenia textbook did not mention Harding’s Vermont study, Harrow’s research, or any of the studies documenting poor long-term antipsychotic outcomes — an omission Whitaker describes as a canonical reference bearing “no relationship to the actual science.”(Whitaker, Robert, 2010)

After more than 50 years of widespread antipsychotic use, no controlled trial had established safe withdrawal protocols, no systematic data existed on what proportion of patients could remain well without drugs, and no guidelines existed for supporting discontinuation — a fundamental gap that the field had not prioritized.(Whitaker, Robert, 2010)

Clinical Context and Limits of This Source

This page draws primarily on Robert Whitaker’s Anatomy of an Epidemic (2010), a journalistic investigation that synthesizes published research and government data. Whitaker’s factual claims — the studies he cites, the statistics he marshals — are drawn from peer-reviewed sources and are not generally disputed. His causal interpretation — that psychiatric medications are a significant cause of rising disability rates — is contested. Selection effects in naturalistic studies, the role of social support and cultural context in cross-national comparisons, and the genuine severity of untreated acute psychosis all complicate the causal picture. The appropriate clinical conclusion is not that antipsychotics should never be used, but that the standard of informed consent and the framework for long-term prescribing decisions should take seriously a body of evidence that the field has not consistently brought to public attention.