VaticanMoncrieffJune2013

Modern medicine: advantages and limits

Joanna Moncrieff,University College London,

Rome, 2013

Drug treatment of mental health problems: a new framework

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1992 1996 2000 2004 2008

antidepressantprescriptions(millions)

Trends in antidepressant prescribing 1992-2010

Trends in prescriptions for stimulants in England

• “People with depression may have an imbalance of the brain’s neurotransmitters” Eli Lilly, 2003

• “Paxil CR helps balance your brain’s chemistry” PaxilCR.com, 2009

Models of drug action

Disease centred model Drug centred model

Drugs correct an abnormal brain state

Drugs create an abnormal brain state

Drugs as disease treatments Psychiatric drugs as psychoactive drugs

Therapeutic effects derived from effects on (presumed) disease pathology

Useful effects are a consequence of the drug induced state

Paradigm: insulin for diabetes Paradigm: alcohol for social anxiety

Psychoactive drugs

• Produce altered mental and physical states

• Tolerance and withdrawal effects

Classification of psychiatric medications

Pre 1950s:

• Sedatives

• Stimulants

Post 1950s:• Antipsychotics• Antidepressants• Anxiolytics• Mood stabilisers• Hypnotics

Different assumptions- different values

Disease centred model- assumes benefit

Drug centred model- assumes harm

• No evidence that psychiatric drugs reverse underlying chemical imbalances or other biological abnormalities

We do not know the mechanism of any mental disorder

• Dopamine hypothesis of schizophrenia

• Serotonin or noradrenalin hypothesis of depression

• No conclusive independent evidence for any of these or other theories

So how do psychiatric drugs work? The drug-centred model

• Direct effect of psychoactive and physical effects

• Amplified placebo effects

Using drugs in a drug-centred manner

Need to know full range of:• Mental effects• Physical effects• Short-term effects• Long-term effects• Withdrawal effects

and…

• Are the effects a drug produces useful in an individuals particular situation?

• Do useful effects persist with continued use?

• Do they out-weight the adverse effects?

• Are there alternatives?

Effects induced by stimulant drugs (Ritalin, amphetamine, atomoxetine, etc)

• Increase attention on repetitive tasks• Suppress exploratory, inquisitive and social

behaviour• Stereotypic behaviours or perseveration

• May improve performance on simple tasks in short-term

• No evidence that they improve performance on complex tasks or over long-term

Adverse effects of stimulants

• Growth restriction (4cm in MTA study at 3 years)

• Raise blood pressure, pulse, and associated with sudden cardiac death

• Psychological effects: ‘zombie’ effect, psychosis, depression

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Psychoactive effects of some modern antidepressants (SSRIs and venlafaxine)

• Drowsiness, lethargy• Cognitive impairment• Emotional blunting• Reduced libido

• Agitation and anxiety• Tension• Insomnia• Anger, Aggression, Emotional instability• Impulses to self harm/suicide

• Not pleasant for volunteers

Adverse effects of antidepressants (SSRIs etc)

• Sexual dysfunction

• Prolonged withdrawal

• Suicidal preoccupation (related to activation and emotional blunting)

Antipsychotics

• Physical and mental suppression (similar to Parkinson’s disease for older drugs)

• Emotional dampening or indifference

• Used as animal tranquillisers

Adverse effects- antipsychotics

• Irreversible, neurological damage (tardive dyskinesia) with long-term use

• Brain shrinkage• Weight gain and diabetes• Cardiovascular disease • Sexual impairment• Dysphoria• Tardive psychosis?• Cognitive decline? • ?death

National trends in office-based visits by children and adolescents that included antipsychotic treatment, 1993-2002 (Pincus et al, 2006)

A drug-centred perspective on use of psychiatric drugs

• Psychiatric drugs are psychoactive drugs

• They put people into altered, drug-induced states

• They may suppress symptoms in short-term

• They have unpredictable and unresearched effects in long-term

• Stopping them may produce its own difficulties

• We should presume harm not benefit