Substance Misuse and Prescribing
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Transcript Substance Misuse and Prescribing
Introduction to
Substance Misuse
Objectives
1.
2.
Substance history taking and identification of
dependency
Increase awareness of the effects of
commonly abused substances
3.
Knowledge of withdrawal symptoms
4.
Co-morbidity issues
5.
Case scenarios to discuss possible
management strategies
Substance History Taking
Ask all patients if they drink alcohol. Can use alcohol screening questionnaires: CAGE – 4 questions,
Alcohol use disorder AUDIT or FAST alcohol screening test
Ask about other substances
Legal
Prescribed
Illegal
Over the counter
How much, how often, route of use, length of use
Withdrawal symptoms?
How does it affect life, work, family?
Are they receiving support?
Do they think they have a problem?
Do they want help?
Get history from informant if possible
Check other records if available
Be aware of how to refer top local services if dependent
Consider joint working between CMHT and SMS
Dependent Use
Daily or almost daily use
Tolerance to substance
Craving and loss of control over use
Withdrawal symptoms
Major effect on functioning
Rapid reinstatement after stopping
Use ongoing despite harm to self and others
Intoxication
Definition
A condition following use of a psychoactive substance which results in:
Disturbances in level of consciousness
Disturbed cognitive functioning
Changes in affect or behaviour
The disturbances are directly related to the pharmacological effects of the
substance and resolve over time.
Intoxication can lead on to overdose, which can be fatal. Poly-drug abuse is
common in fatal overdoses in opiate addicts with alcohol and benzodiazepines
often implicated.
Individuals with a known substance misuse problem are at high risk of intoxication
with a range of substances, not only the substance which is their primary problem.
Alcohol
1 unit is 8g and is eliminated in approx. 1 hour
1 unit contained in:
½ pint of 3-4% beer
125ml average strength wine
a single measure of 25ml spirits
Recommended limits:
Women – maximum 14 units per week
Men – maximum 21 units per week
Harmful drinking is:
More than 35 units per week for women
More than 50 units per week for men
40% of alcohol misusers develop acute withdrawal symptoms. These range from minor to severe.
Delirium tremens is uncommon. This starts 48-72 hours after stopping and is a medical
emergency.
Other patients can mostly be managed as outpatients.
Admission to inpatient psychiatric wards for detoxification is not recommended. But this may be
necessary if psychiatric co-morbidity is present. A risk assessment is needed.
Alcohol withdrawal
Acute alcohol withdrawal syndrome following
abrupt reduction or cessation of regular high
alcohol intake appears as soon as the blood
alcohol level decreases significantly.
Symptoms usually peak at 12-30 hours and
subside by 48 hours.
Delirium tremens occurs in <5% of individuals
and if untreated delirium tremens has a
mortality of 15%.
Basic management of alcohol withdrawal
All patients with suspected alcohol misuse should be
monitored for signs of withdrawal
Using CIWA-AR scoring regularly (ie 2 hourly with physical obs
for first 24 hours)
CIWA-AR score should inform Chlodiazepoxide dosing.
PRN choldiazepoxide should be prescribed for the first 2448hours if CIWA-AR score is >10. This dosing can be given up to
hourly to a maximum of 200mg a day if the CIWA remains above
10.
After 48hrs NO PRN should be given, but the daily TOTAL dose
needed over the last 48 hrs divided into 4 doses and gradually
reduced in a regimen over the following 5-7 days
Only in EXCEPTIONAL circumstances will an individual need a
detox longer than 7 days
This approach reduces under and over
prescribing of Chlodiazepoxide
Betsi-wide guideline regarding alcohol
detoxification prescribing should be ready
within the next few months
Basic Management of alcohol withdrawal
All patients with alcohol withdrawal should be
given thiamine orally
Patients with signs/symptoms of
wernickes/korsakoffs should be given Pabrinex
Prophylactic Pabrinex should be given in those
at high risk (i.e. malnourished individuals)
Night sedation should NOT be prescribed
routinely (NICE guidelines)
Additional benzodiazepines should NOT be
prescribed routinely (NICE guidelines)
Psychoactive Substances
Stimulants
Depressants
Hallucinogen
Hallucinogens
s
Cannabinoids
Cocaine
Ecstasy
Amphetamine
Heroin
Benzodiazepines
Methadone
LSD
Magic
Mushrooms
Cannabis
Benzo Fury
Gogaine
Mephedrone
BZP
Dextromethorphan
GBL
Etizolam
Ketamine
Methoxetamine
Tryptamines
Spice
Black Mamba
Clock Work Orange
Ketamime
Action blocks activation of non-completive N-methyl-D-aspartate receptors
(NMDA)
Abuse by snorting or injecting
Hallucinogenic dose is 30 mg orally
Reduces sensation and movement
Feeling of detachment (K-hole)
Hallucinations
Toxic confusional state
Bladder damage with regular use
No physical withdrawal symptoms
But ?clinically useful
Low dose ketamine infusion for treatment resistant depression
First UK study in Oxford reported in J. Psychopharmacology April 2014
Cocaine
Cocaine is the psychoactive alkaloid of the coca plant
Naturally occurring local anaesthetic
Well absorbed, peak concentration
5-10 mins after IV use
5-10 mins after smoking
60 mins after snorting
Shorter acting than amphetamines
Enhances dopamine activity
Blocks dopamine re uptake into nerve terminal
Direct action on cell membranes blocking nerve impulses (local anaesthetic
action)
Also blocks re-uptake of 5HT and noradrenaline
Acts on vertical tegmental area
Effects of cocaine on user
Euphoria and mood elevation
Increased energy and self confidence
Enhances talkativeness
Enhances mental alertness
Alleviates fatigue… BUT…
At HIGH DOSES or when USE is CHRONIC, adverse effects are more common
Restlessness and nervousness
Excitability
Aggression
Suspicious and paranoid thoughts
Loss of libido
Hallucinations
Delusional thoughts
Not all patients develop withdrawal symptoms.
Withdrawal symptoms are more likely in:
Long term higher dose patients
Patients with a history of drug and alcohol dependence
Patients with dependent and avoidance type personality
types
Basic management of opiate
withdrawal
Symptomatic treatment is recommended (This can be
monitored using the COWS scoring)
Paracetamol and ibuprofen for muscle aches
Loperamide for diarrhoea
Mebeverine for abdominal pain
Night sedation (low dose and short term)
Lofexidine can also be used
DO NOT commence on opiate replacement therapy such
as methadone as this will need to be initiated and
followed up by SMS services, instead manage
symptomatically and refer to SMS ASAP
Methadone
Initiated by specialist services ONLY
Its effects are longer acting than those of morphine, which may result
in a cumulative effect – thus it should not be given more than twice a
day, it is also less sedating
Well absorbed orally and prescribed as liquid (green) 1mg in 1ml
Doses of 50mg or less can be fatal in non tolerant patients
It is an excellent analgesic
When seeing an inpatient on methadone please ensure SMS services
are aware of their admission
DO NOT PROVIDE METHADONE TTOS (liaise with SMS and community
pharmacy to facilitate methadone upon discharge)
Methadone for opiate dependency
Methadone is a synthetic compound with pharmacological
action similar to that of morphine and heroin, almost equal
in addiction liability
“Methadone is a valuable drug in the treatment of opioid
dependence. But it is two-edged in that if carelessly
employed it can add to the toll of opioid-related deaths.”
….Reducing Drug Related Deaths,2000
Buprenorphine
(Subutex) (Suboxone)
Also known as temgesic (Subutex) – this is for you to be aware of if seeing
individuals on this drug, again we would ask that SMS be informed if patient
admitted and informed of discharge so medication can be arranged – DO NOT
PROVIDE TTOS of suboxone/subutex for substance misuse clients
Taken sublingually – first pass metabolism in liver
Maintenance dose for opiate addicts, 2 mgs – 32 mgs – average maintenance dose
around 12 mgs
Negative on screening for opiates
Long acting x 1/day
Partial agonist
µ Agonist
Kappa Antagonist
As effective as oral methadone on various trials
Use of Suboxone as less abuse potential
Dual Diagnosis – some findings
Rates of substance misuse are much higher in people with psychosis
than in the general population
The main problem substances are cannabis and alcohol, if nicotine is
excluded
Misuse is more usual than dependency
Between 30-50 % of patients known to drug services fulfil criteria for a
psychiatric diagnosis, mostly anxiety/depression
Relevant issues for
Dual Diagnosis Patients
Problems in diagnosis – often have more than 2 diagnoses
Patients perceived to be difficult, with a poor prognosis and unpopular
with service providers
Demarcation disputes between drug services and general psychiatric
services – many fall through the net of service provision
Patients may conceal their substance use from professionals, fearing
stigma and discrimination
Possible Relationships between Substance
Misuse and Psychotic Symptoms
Intoxification
e.g. amfetamines, LSD, cannabis
Withdrawal states
e.g. alcohol, benzodiazepines
Hallucinosis
e.g. alcohol
Confusional states
e.g. Crack/cocaine, LSD
Exacerbation of underlying psychosis (often small quantities)
e.g. cannabis, alcohol, amfetamines
Drug induced psychosis (symptoms continue after no evidence of drug in body)
e.g. amfetamines
Clinical Scenarios
1.
Patient is verbally threatening intoxified with
alcohol and expressing suicidal ideation
2.
Patient on oral Methadone has developed
psychotic symptoms
3.
Patient has lost Methadone and Diazepam
prescription
Substance Misuse and
Prescribing
Dr Sue Ruben
August 2011
Alcohol Use Disorder
Identification of alcohol problems
Varied clinical presentation including:
Depression
Anxiety
Fatigue, debility, memory problems
Gastro-intestinal symptoms
Liver disease
Marital disharmony
Onset of fits in adult life
Frequent absences from work, particularly Monday mornings
Alcohol abuse often complicates the picture in patients with psychiatric
problems and leads to a worse prognosis
Alcohol Use Disorder
Alcohol use disorders involve drinking above
recommended limits
Recommended limits are based on daily or
weekly total alcohol consumption in units
1 unit of alcohol = 10ml ethanol (but most
drinkers do not think in terms of ethanol
volume or alcohol units)
Alcohol Units
Alcohol Use Disorder
The pattern of drinking and the total weekly
consumption of alcohol are important
determinants of alcohol related harm:
Hazardous alcohol use
Harmful alcohol use
Alcohol dependence
Binge Drinking
Classification of Alcohol Use Disorder
Hazardous Drinking
Pattern of alcohol consumption that may
eventually cause harm i.e. drinking above
sensible or recommended limits:
>14 units a week for women (3 units a day)
>21 units a week for men (4 units a day)
Classification of Alcohol Use Disorder
Binge drinking – regularly drinking twice the
daily recommended limit i.e. 8 or more units a
day for men or 6 or more units a day for women
Binge drinking may fall into hazardous or
harmful categories
Classification of Alcohol Use Disorder
Harmful Drinking
Pattern of alcohol consumption that is already
causing damage to the person’s physical or
mental health (50 units men or 35 units
women)
Damage may be acute (acute pancreatitis) or
chronic (alcohol related brain damage)
Despite evidence of alcohol related problems
patients do not usually seek treatment
Classification of Alcohol Use Disorder
Alcohol Dependence Syndrome
A strong desire or sense of compulsion to drink
Difficulties in controlled alcohol intake
A psychological withdrawal state, includes:
Shaking and tremor
Anxiety symptoms
Insomnia
Sweating
Morning nausea and vomiting
Tolerance
Progressive neglect of alternative pleasures or interests
Persistent drinking despite clear evidence of harmful consequences
Blood Alcohol Values and Their
Effects on Normal Drinkers
BAC (mg/dl)
20
40
60
80
100
120
150
300-400
450 and above
EFFECTs
Light drinkers begin to feel some effects
Begin to feel relaxed
Judgement somewhat impaired, drivers TWICE as
likely to have an accident
Co-ordination and driving skilled impaired,
beginnings of disinhibition
Reaction time and self control impaired,
accidents 7 TIMES more likely
If drinking rate is fast vomiting can occur
Slurred speech and staggering, accidents 25 TIMES
more likely
Loss of consciousness likely
Death can occur
Alcohol Misuse and Dependence
Alcohol History Taking
Consider alcohol as a possible cause of symptoms
CAGE questionnaire
Have you ever felt you should Cut down your drinking?
Have people Annoyed you by criticising your drinking?
Have you ever felt bad or Guilty about your drinking?
Have you ever had a drink first thing in the morning to steady your
nerves and get rid of a hangover (Eye opener)?
Carry out AUDIT score…
Alcohol Use Disorder Identification Test
(AUDIT)
Please circle the answer that is correct for you:
1.
How often do you have a drink containing alcohol?
Never
Monthly
2-4 times 2-3 times
or less
a month
a week
4 or more times
a week
2.
How many standard drinks containing alcohol do you have on a typical day of drinking?
1-2
2-4
5-6
7-9
10 or more
3.
How often do you have six or more drinks on one occasion?
Never
less than monthly
monthly
weekly
daily
4.
How often during the last year have you found that you were not able to stop drinking once you
have started?
Never
less than monthly
monthly
weekly
daily
5.
How often during the last year have you failed to do what was normally expected from you
because of drinking?
Never
less than monthly
monthly
weekly
daily
6.
How often during the last year have you need a drink in the morning to get yourself
going after a heavy drinking session?
Never
less than monthly
monthly
weekly
daily
7.
How often during the last year have you had a feeling of guilt or remorse after drinking?
Never
less than monthly
monthly
weekly
daily
8.
How often during the last year have you been unable to remember what happened the night
before because you had been drinking?
Never
less than monthly
monthly
weekly
daily
9.
Have you or someone else been injured as a result of your drinking?
No yes, but not in the last year
yes, during the last year
10.
Has a relative or friend or a doctor or other health worker been concerned about your drinking or
suggested you cut down?
No yes, but not in the last year
yes, during the last year
(scoring 0-4 for each answer 0 – never, 4 – daily)
A score of 8 or more is associated with harmful or hazardous drinking
A score of 13 or more in women, and 15 or more in men is likely to indicate alcohol dependence
Alcohol Misuse and Dependence
Detoxification
If a patient is physically dependent, they usually require medication to
minimise withdrawal symptoms
This may not require in-patient treatment unless:
History of fits
High risk of delirium tremens
Very poor physical health/lack of social stability
Co-morbidity
For home detoxification, the patient needs to:
Show good motivation to detoxify
Agreed with Substance Misuse Team to oversee the withdrawal
No history of abuse of prescribed medication
Use
Librium (Chlordiazepoxide)
Starting dose between 10 – 20 mgs QDS – max
200mg/day
Reduce to zero over 5 – 7 days – once controlled
No routine night sedation
Vitamin B supplements
Rest and high fluid intake
Alcohol Misuse and Dependence
Post Detoxification
Avoid prescribing:
Benzodiazepines
Chlormethiazole
Routine night sedation
(risk of dependency)
(Never in a community setting)
Assess mood:
If depressive symptoms prominent or mixed depression/anxiety and
panic after 2 – 3 weeks alcohol free, consider anti depressants
Repeat LFT’s, FBC – Gamma GT should improve if alcohol free
Disulfiram and Acamprosate can be used to assist staying alcohol free
Consider AA, counselling or other support services available locally
Monitor the patients’ progress on a regular basis
If relapse occurs may require referral to specialist services
Alcohol Misuse and Dependence
Management
Early intervention in primary care
Advice about sensible drinking
Useful for patients who are at early stage of alcohol
problem
Motivational interviewing techniques
Helps patients to reach a decision to change
Give feedback about risks
Emphasis on personal responsibility
Give direct advice about drinking
Discuss a menu of options for changing drinking
Remain empathic towards the patient
Set and agree goals which are attainable short-term and have
positive rewards for patients
Involve the family, if possible
Enhance self esteem and hope
Use other agencies e.g. counselling, AA
Be prepared to confront and challenge the patient of
necessary
Follow up support
Delerium Tremens
Occurs in severe alcohol withdrawal in approx 5% of patients
It is a toxic confusional state and can be life threatening
Is often associated with other medical conditions
Requires treatment in a general medical setting
Symptoms
Clouding of consciousness and confusion
Vivid hallucinations
Agitation and tachycardia, hypertension, sweating and fever
Marked tremor
Paranoid ideation
Symptoms peak 72-96 hours after last drink
Wernicke’s Encephalopathy
Caused by acute Thiamine deficiency
Classic symptoms are
Opthalmoplegia
Ataxia
Confusion
Always consider during alcohol detoxification if patient has any of these
signs
Must have parenteral B complex (Pabrinex) not oral Thiamine for
3-5 days
Benzodiazepines
Substance Misusing Patients and Benzodiazepines
Abuse of benzodiazepines is very common in patients with substance
misuse problems (both drugs and alcohol)
Many display a pattern of binge use with periods of abstinence and are
not “dependent” on the medication
Some injecting drug users will inject benzodiazepines
Substance misusers often obtain supplies from patients who are not
themselves substance misusers
For heroin addicts, the use of benzodiazepines in association with
heroin increases the risk of death in overdose
Benzodiazepine prescribing should be avoided in this patient group
Benzodiazepines
Main therapeutic Uses
1.
2.
3.
4.
Anxiolytic (not a first line treatment for anxiety disorders)
Treatment of insomnia – short term
Sedative e.g. pre-operative
Management of agitation in psychosis
Problems associated with benzodiazepines
Sedation
Cognitive impairment, poor concentration, poor short term memory
Tolerance, dependence with dose escalation
Withdrawal symptoms
Abuse and diversion into the illicit market
Good Prescribing Practice of
Benzodiazepines
Use non-drug therapies wherever possible for anxiety and insomnia
Identify depression which is common and where appropriate prescribe
anti depressants
Only prescribe for a short time with regular reviews
Discuss the “pros” and “cons” with the patient
Do not prescribe more than one benzodiazepine at a time
Always be aware of the risks of misuse of the medication and possibility
of diversion to the illicit market
Try and prescribe as low dose as possible
Develop a Prescribing Policy within each therapeutic setting
Benzodiazepines
Managing Withdrawal from Benzodiazepines
Identify suitable patients
Transfer patient to a long acting benzodiazepine (usually diazepam)
prior to withdrawal
Agree a treatment plan with the patient with dose reductions at regular
intervals
Be prepared to be flexible
Any overall dose reduction is positive
Offer psychological support and non-drug therapies:
Anxiety management
Relaxation therapy
Cognitive restructuring
Exercise
Acupuncture
Symptoms of Benzodiazepine Withdrawal
Anxiety
Sweating
Insomnia
Headache
Tremor
Nausea
(poor appetite)
Feelings of unreality
Hypersensitivity to stimuli
Abnormal sensations within
the body
Withdrawal psychosis
Epileptic seizures
Not all patients develop withdrawal symptoms.
Withdrawal symptoms are more likely in:
Long term higher dose patients
Patients with a history of drug and alcohol dependence
Patients with dependent and avoidance type personality
types
Prescribing for Heroin Addicts
1.
2.
3.
4.
5.
6.
Opiate withdrawal is not a life threatening condition opiate toxicity is
Do not initiate opioid substitution treatment in general adult
psychiatry without the support of substance misuse services for full
assessment and plan
If patient is on substitute medication before continuing it, check with
prescriber and/or pharmacy to verify dose
If uncertain about compliance consider dose reduction or split dose,
ask patient what dose they take
ECG if adding antipsychotics to methadone (QT interval)
Risk of respiratory depression when co-prescribed sedative
medication - increase levels of observation and do not prescribe if
patient appears intoxified e.g. slurred speech, ataxia, confused
Methadone
Methadone is a synthetic compound with pharmacological action
similar to that of morphine and heroin, almost equal in addiction liability
“Methadone is a valuable drug in the treatment of opioid dependence.
But it is two-edged in that if carelessly employed it can add to the toll of
opioid-related deaths.”
….Reducing Drug Related Deaths,2000
Methadone
Its effects are longer acting than those of morphine, which may result
in a cumulative effect – thus it should not be given more than twice a
day, it is also less sedating
Well absorbed orally and prescribed as liquid (green) 1mg in 1ml
Doses of 50mg or less can be fatal in non tolerant patients
Methadone
Expected Outcome
Reducing drug use
Reduced criminal activity
Reduced mortality
Improved physical and mental health
Reduced risk behaviours for HIV, HCV and other blood-borne pathogens
and reduced risk behaviours for HIV and STD’s
Methadone
Benefits of Methadone
This occurs when methadone is given in adequate dosage, with good
supervision and in the context of psychosocial support
Often supervised in community at local pharmacy
Start with low dose and titrate up
Doses vary between 10 mgs – 120mgs/day
Better outcomes with doses over 60 mgs/day
Buprenorphine (Subutex)
Also known as temgesic (subutex)
Taken sublingually – first pass metabolism in liver
Maintenance dose for opiate addicts, 2 mgs – 32 mgs – average
maintenance dose around 12 mgs
Negative on screening for opiates
Long acting x 1/day
Partial agonist
µ Agonist
Kappa Antagonist
As effective as oral methadone on various trials
Buprenorphine
Advantages
Safer in overdose
Less euphoriant effects
May be easier to detox from
?Some anti-craving action
Rapid dose titration
Good alternative for patients
who do not want methadone
Increasingly used as an
alternative to methadone
Disadvantages
Hard to reverse with Naloxone
Readily abused intravenously
and snorted
More expensive
More difficult to supervise
Have to be in moderate
withdrawal prior to first dose
Higher dropout rates early in
treatment
Side effects include
hallucinations
?Caution in psychotic patients
?Hepatotoxicity – advise LFT’s
prior to prescribing
Crack Cocaine/Amfetamines
Increase in all areas in particular urban/inner city
Reduced price, often sold with heroin
Often the gateway drug point prior to heroin
Often used intravenously (speedballing with heroin)
Abuse more common than dependency
Cocaine mixed with alcohol makes cocethyelene
No evidence based pharmacotherapy for cocaine or amfetamine
dependency
Some week evidence for acupuncture
Treatment services mostly consist of psychosocial interventions
Detoxification from opiates
Choice of treatments:
1.
2.
3.
4.
Methadone reduction
Lofexidine
Subutex (buprenorphine)
“Cold turkey)
Symptomatic relief:
1.
2.
3.
4.
5.
6.
7.
Anti-nausea drug
Anti-diarrhoea drugs
Anti-spasmodic drugs
Night sedation (but be aware of risks of dependence)
Acupuncture and E.S.T
Massage/reflexology
Exercise
Relapse Prevention
Opiate dependence is a chronic relapsing condition and
relapse is common especially in the first three months
after detox
To reduce risk of relapse:
1.
Naltrexone
2.
Psychological and social support
3.
Residential rehabilitation
This is to certify that:
.........................................
Has reviewed/completed
.......... Substance Misuse.................
Date
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