Download Module 4: Interaction of

Module 4: Interaction of
Objectives
• To be aware of the possible reasons why
dual diagnosis occurs
• To be aware of the specific effects of
substances on mental health
• To be aware of how substance use affects
prescribed psychiatric medications
Dual Diagnosis Capabilities
• Education and Health Promotion: Be able
to offer basic but accurate and up to date
information and advice about effects of
substances on mental and physical health
and vice versa. Dual Diagnosis Capability
8 level
Possible links between mental
health and substance use
• Common Causal factor: An underlying factor that increases
likelihood of developing both a substance use disorder and mental
illness e.g. past trauma or a genetic predisposition.
• Mental Illness leads to substance use. People with mental illness
are more likely to develop substance use problem than those in
general population. For example, mental illness may lead to the use
of substances as a coping strategy or self-medication.
• Substance use causes mental illness. Heavy substance use
clearly leads to temporary states that mimic psychosis (drug induced
psychosis) and/or lead to problems such as depression.
• Bi-Directional Theory. Mental health symptoms and substance
use affect the course of each other in a constantly evolving spiral.
Alcohol and mental health
• Most commonly used drug by those with mental
health problems
• Depression
• Anxiety and paranoia
• Morbid jealousy
• Delerium Tremens (confusion and psychosis)
• Organic brain damage
• For people with schizophrenia
– May increase psychotic symptoms
– Reduces effectiveness of psychiatric medication
Cannabis and Mental Health
• Second most commonly used drug by those with mental health
problems.
• In any user cannabis use can cause anxiety, panic attacks, and
extreme, but short lived paranoia.
• Temporary cannabis psychosis
• Some evidence that regular cannabis use is a contributing factor to
the onset of schizophrenia:
– cannabis use in teenage years is a predictor of future mental illness.
– The earlier a person begins smoking and the heavier they smoke, the
greater the risk of future development of schizophrenia.
– This effect seems to be stronger in individuals who have other
vulnerability factors (Arseneault et al, 2004).
• People with schizophrenia who smoked cannabis were more likely
to relapse quicker and have worse symptoms than those who didn’t
use cannabis. (Linszen et al 1994)
Cocaine and Mental Health
• Less commonly used, mostly urban areas.
• Cocaine increases levels of dopamine in the brain.
(Dopamine-chemical messenger in the brain; high levels
have been associated with psychotic symptoms).
• Even people without a history of psychosis can
experience a transient but severe psychosis (“druginduced psychosis”).
• Cocaine use in people with schizophrenia seems to
increase both severity of symptoms and likelihood of
psychiatric relapse when compared to non-drug using
people.
• Can exacerbate or induce a depressive illness as it may
deplete natural serotonin levels over time. (Serotonin is
the chemical messenger in the brain that is reduced in
people with depression)
Opiates and Mental Health
• Less than 10% of people with schizophrenia use opiates:
– relapse of psychotic symptoms commonly occurs during or
immediately after withdrawal of opiate or substitute (methadone).
– Opiates have mild antipsychotic effects, and therefore use may
mask psychosis.
– People with acute psychosis should not undergo a rapid
detoxification of opiates; the focus of care should be on the
stabilisation of their mental state and substitute opioid
prescribing (Royal College of Psychiatrists, 2002).
• Opiates: more commonly used by people who also have
depression, anxiety, and/or personality disorders rather
than psychotic illness.
Anti-depressants and Substance
use
• Alcohol will reduce effectiveness of antidepressants- is it worth prescribing?
• Mono oxidase inhibitors are
contraindicated with stimulants such as
amphetamines (hypertensive crisis)
• drinking increases risk of impulsive selfharm therefore avoid “toxic” antidepressants such as tricyclics
Anti-psychotics and Substance Use
• People with dual diagnosis are at greater risk of extrapyramidal sideeffects and tardive dyskinesia (movement disorders).
• People who use drugs and alcohol have worse outcomes on typical
antipsychotics (e.g. chlorpromazine)
• Atypicals prefered due to low profile of EPSE (e.g. Olanzapine)
• Alcohol and other drugs may reduce plasma level of antipsychotic
(may need higher dose)
• Antipsychotics may help provide a level of protection from adverse
effects of substances by blocking dopamine receptors
• No need to discontinue anti-psychotics even if person regularly uses
drugs.
• However, substance use mixed with anti-psychotics may cause drop
in blood pressure, increased sedation, and high temperatures so
regular health monitoring is vital.
Benzodiazepines and Substance
Use
• Benzodiazepines (tranquillisers) such as diazepam are
highly addictive and very difficult to withdraw from.
• High doses of benzo’s act like alcohol leading to
paranoia, disinhibition and aggression.
• They interact with other depressants (alcohol, heroin etc)
increasing sedative effect and toxicity
• If mixed with depressants, can lead to accidental
overdose and death.
• Have a high “street value”.
• Prescription of benzo’s should be for short term (2
weeks) treatment for anxiety only.