Psychostimulants

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Psychostimulants
Psychostimulants
GPs and Psychostimulants
• GPs are increasingly likely to see
psychostimulant use
• Most commonly used illicit drug after
cannabis
• GPs are well placed to identify, manage
and minimise health problems that can
arise from psychostimulant use.
Psychostimulants
Psychostimulants Defined
• The term ‘psychostimulant’ describes a diverse range
of naturally occurring and synthetically produced
drugs
• Also known as Amphetamine Type Stimulants (ATSs)
• Main effect – stimulates CNS activity
• Includes many commonly used substances/drugs
• Each drug varies in strength and effect, although each
has features in common
• Most people have used a psychostimulant in the last
24 hours!
Psychostimulants
Psychostimulants May Be….
1. Synthesised Compounds
Pharmaceuticals
Illicitly produced
Pseudoephedrine
Dexamphetamine
Diethylpropion (Tenuate®)
Methylphenidate (Ritalin®)
Amphetamine sulphate i.e. speed
Methamphetamine
e.g. ice, meth, crystal
Amphetamine-type substances
e.g. MDMA (Ecstasy), PMA, MDA
etc.
2. Naturally Occurring Compounds
Tobacco (nicotine)
Adrenaline
Khat
Cocoa (chocolate)
Caffeine
Cocaine
Guarana
Others...
Psychostimulants
Psychostimulant Forms (1)
Common
Form
Chemical
Composition
Powder
Amphetamine
also called
sulphate or
speed, goey, methamphetamine
whizz fast
quick
Appearance
Cost
‘Route’
Administered
Fine to
$50-100 Snorted,
crystallised
/gram
swallowed,
coarse powder
injected, shelved
White-to yellow,
orange or pink
Crystal
Methamphetamine ‘Crushed ice’
$50
also called
hydrochloride
large translucent /point
ice
to white crystals
crystal
or coarse
meth
powder
Shabu, glass
Smoked, snorted,
swallowed,
injected
Psychostimulants
Psychostimulant Forms (2)
Common
Form
Chemical
Composition
‘Base’
Free-base form of
also called methamphetamine
wax, paste,
point, pure
‘Pills’
Appearance
Cost
Damp, sticky
$30-50 /
gluggy powder, ‘point’
paste oily
yellow, red
brown
Dexamphetamine Tablets
methylphenidate
(Ritalin®),
diethylpropion
(Tenuate®)
‘Route’
Injected,
swallowed,
smoked,
snorted
$30-40 / Injected,
tab (illicit swallowed
supply)
Psychostimulants
Patterns of Use
• Use tends to:
– occur in social settings among diverse groups
of people
• Trends indicate psychostimulants are increasingly
injected
• Few patients will meet the criteria for dependence,
however:
– heavy users tend to use in a ‘binge’ pattern or a
‘run’ usually followed by a period of abstinence
– heavy users are frequently polydrug users, with
many using depressants to alleviate symptoms
associated with the ‘come down’.
Psychostimulants
Pharmacology
• Variable chemical compositions result in
differences in pharmacological activity
across psychostimulant types
• Genetic differences in metabolism
• Half life of psychostimulants differ:
– amphetamine 12–36 hours
– methamphetamine 8–17 hours
– (ecstasy) MDMA 7–9 hours
– cocaine 45–90 minutes.
Psychostimulants
Synaptic Activity
Psychostimulants
Meth/Amphetamine Effects:
Onset and Duration
Injection
Intranasal
Effect
Intensity
Swallowed
Amphetamine
1 min
3min
60 min
6 hours
1 min
3min
20 min
30 min
Cocaine
Duration of effect
Psychostimulants
Amphetamine Effects
Mild
Feel good
Alert
Energy
Confidence
Sleeplessness
Reduced appetite
Dry mouth
Moderate
Feel great
Increased libido
Increased
stamina
No need for sleep
Crash
Suspicion
Headache
Teeth grinding
Anxiety
Toxic
Extreme agitation
Incoherence
Increased temperature
Dehydration
Thought disorder
Violent aggression
Stroke
Heart attack
Psychostimulants
Psychostimulant Cycle of Use
Acquisition
Administration
Intoxication
How and where can GPs
assist in reducing harms?
Cessation
Crash /
Withdrawal
Intoxicated
behaviour
Psychostimulants
Psychostimulants
Psychostimulants
Psychostimulants
‘Typical’ Pattern of Use
Using
Stopping
Symptom Severity
High
Thought disorder
Agitation
Insomnia
Suspicion
Increased energy
Feel good
Exhaustion
Depression
Oversleeping
Overeating
No craving
Low
-7
0
Anhedonia
Lack energy
Anxiety
Sleepless
High craving
2
5
Flat mood
Emotionally fragile
Episodic craving to cues
15
20
25
30+
Days
Pead, et al. (1996, p. 37)
Psychostimulants
Assessment Points
• Occupation
• Age
• Social activities
• AOD History
– patterns of use, drug type, route, other drug use
• Physical health (e.g. stability of weight)
• Mental health (emotional lability, psychosis / paranoia)
• Current level of intoxication / evidence of withdrawal
• Laboratory investigations.
Psychostimulants
Courtesy of Dr. John Sherman, St. Kilda Medical Centre
Psychostimulants
Psychostimulants
Courtesy of Dr. John Sherman, St. Kilda Medical Centre
Psychostimulants
Psychostimulants
Management of Toxic Reactions
Priorities are:
• maintain airway, circulation, breathing
• control elevated body temperature
(hydration, cold water, ice)
• control seizures (IV diazepam)
• manage psychotic symptoms (antipsychotics)
• reassurance, support, comfort, minimal stimulation.
Treatment depends on patient’s condition on presentation.
Psychostimulants
Case Study
Rory, a 24 year old student, presents with persistent
headache, lethargy, and unexplained weight loss. He is
‘burning the candle at both ends’, working (in a bar) and
studying, and states that ‘life is pretty hectic’ at present.
Speed helps him get things done.
Describe a brief intervention for Rory.
Psychostimulants
Psychostimulant Withdrawal
Crash
(Days 1–3)
 exhaustion
 depression
 oversleeping
 no cravings
Peak symptoms
(Days 2–10)
 dysphoria
 lack energy
 increased appetite
 generalised aches
and pains
 re-emergence of
mild psychotic
features, including:
misperceptions
paranoid ideation
hallucinations
anxiety.
Residual symptoms
(from 1–8 weeks)
 episodic craving
 insomnia
Fluctuating:
 irritability
 agitation
 restlessness
 dysphoria
 lethargy
 amotivation
 sleeplessness
 high craving
From Pead et al. (1996, p. 84)
Psychostimulants
Withdrawal Treatment
• Immediate withdrawal treatment
– setting (home withdrawal, outpatient, or inpatient)
– supportive environment, information and
reassurance
– provide ongoing monitoring
– pharmacotherapies for symptomatic relief
– plan long term management strategies
• Planning for prolonged withdrawal
– anticipate it will be prolonged
(i.e. affecting sleep, mood, cravings)
– plan for lapse and relapse
– pharmacotherapies (short and long term)
– prepare harm reduction strategies.
Psychostimulants
Pharmacotherapies
For Psychostimulant Withdrawal
• Aim to decrease discomfort
• Benzodiazepines
– assist sleep or reduce anxiety and agitation
– avoid long term prescribing
• Antidepressants
– tricyclic antidepressants are generally not
helpful
– SSRI’s may be helpful but symptoms generally
resolve within a week of withdrawal
• Antipsychotics
– available research shows limited efficacy.
Psychostimulants
Case Study
Kylie, a 33 year old lawyer, recently discovered she
was pregnant. She has an active work and social life,
and consequently, tends to eat poorly. The pregnancy
was unplanned. She is concerned about the health of
her baby, and her lifestyle that precludes regular eating
habits.
How would you incorporate an AOD history into
your consultation?
What triggers may lead you to suspect
psychostimulant use?
Psychostimulants
Cocaine
•
•
•
•
•
•
Alkaloid from plant leaf of Erythroxylon coca
Known as coke, charlie, snow, okey doke
Sold in ‘lines’
CNS stimulant with local anaesthetic actions
Also stimulates SNS
Blocks reuptake of dopamine, noradrenaline and
serotonin.
Cocaine
Crack
Crack in vials
Psychostimulants
Cocaine: Patterns of Use
People who use cocaine tend to:
– be middle class, well educated professionals
who snort
– be injecting polydrug users, occasionally using
‘speedballs’
– use alcohol to enhance cocaine effects
Patterns:
– usually injected or snorted, occasionally smoked
– ‘binge’ or a ‘run’
– bingeing patterns arise from rapid
neuroadaptation.
People who inject tend to use more often, use
greater quantities than snorters, and are at
Psychostimulants
greater risk of harm.
Cocaine: Pharmacology
• Blocks reuptake of
– dopamine (DA)
– noradrenaline
– serotonin
• DA thought to be responsible for reinforcing
effects
• Interaction between cocaine and alcohol can
produce toxic, if not fatal, effects.
Psychostimulants
Cocaine: Metabolism
• Rapid onset of action (2–8 minutes respectively)
• Peak blood levels occur in 5–30 minutes
• Action is brief:
– half-life of 15–30 minutes if injected
– half-life of up to 30 minutes if snorted
• Metabolised by liver, 1–2% excreted unchanged in urine
• Inactive metabolites can be detected in:
– blood or urine for 24–36 hours after use
– hair for weeks to months after use.
Psychostimulants
Cocaine: Acute Effects
 Desired
 Acute low dose

 Euphoria
 Sociable/gregarious,
talkative
 Confidence, control,
energy
 Reduced need for
sleep
 Temporary increase
in functional activity/
efficiency
 Acute high dose
(Overdose)
 Local anaesthesia
 Dilated pupils
 Vasoconstriction
 Increased respiration,
pulse, BP,
temperature
 Stereotyped,
repetitive behaviour
 Anxiety, panic
 Aggression, hostility
 Cardiovascular
events (e.g.
arrythmias, MI)
 Neurological events
(CVA, seizures,
blurred vision,
dizziness, headache)
 Psychological events
(hallucinations,
confusion)
 Stomach pain,
nausea
Psychostimulants
Cocaine: Chronic Effects
• Insomnia
• Depression, anxiety
• Aggression, violence
• Loss of appetite, concomitant weight loss
• Muscle twitching
• Psychosis – paranoid delusions, hallucinations
• Loss of libido / impotence
• Heightened reflexes
• Increased pulse rate.
Psychostimulants
Cocaine: Symptoms of Withdrawal
• Dysphoria (rather than depression) which may
persist (up to 10 weeks). Plus at least two of:
– fatigue
– insomnia / hypersomnia
– psychomotor agitation
– craving
– increased appetite
– vivid unpleasant dreams
• Withdrawal tends to peak 2–4 days following
cessation of use.
Psychostimulants
Cocaine: Withdrawal Management
• Non-stimulating/non-threatening environment
• Possible suicide precautions
• To date, no effective pharmacotherapies for
withdrawal management
• Prescribed medications:
– short term use of benzodiazepines
(anxiety, agitation, promote sleep)
– antidepressants (SSRIs; though continued
cocaine use may precipitate toxic
reactions).
Psychostimulants
Cocaine:
Problems Associated with Use
Physical
• Nasal – e.g. rhinorrhoea,
epistaxis, ulcers, sinusitis,
perforated nasal septum,
risk of HCV transmission
through sharing snorting and
injecting equipment
• IDU – e.g. systemic / local
infections, vein problems
(abscess, cellulitis, phlebitis),
bacterial endocarditis,
BBV transmission
• Cardiovascular complications
• Death.
Psychosocial
• Interpersonal
(relationship discord,
paranoia – irrational
jealousy, alienation)
• Occupational
(absenteeism, job or
productivity loss)
• Financial
• Legal.
Psychostimulants
Psychostimulant Interventions (1)
• Be non-judgmental, do not insist on abstinence
• Engage and retain patient in treatment
• Understand patient’s treatment goals
• Tailor intervention to suit patient, including level and
intensity of referrals
• Offer flexible service delivery, consistent with a
patient’s changing goals and needs
• Provide psychosocial support
• Address concurrent mental health needs; e.g. anxiety,
bipolar, or attention deficit disorders are common with
cocaine use.
Psychostimulants
Psychostimulant Interventions (2)
• Behavioural and psychosocial therapies produce
better results than pharmacotherapies
• Cognitive-Behavioural Therapy (CBT) helps the
patient develop problem solving skills and
strategies to:
– identify high-risk situations
– identify functional drug use
– deal with cravings
• CBT is more effective and longer lasting than less
intensive strategies.
Psychostimulants
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