Amphetamines and other stimulants

 

  • Amphetamine-type stimulants (ice, crystal meth, speed) all have similar effects on the central nervous system
  • Methamphetamine is a stronger stimulant and may cause more severe physical and behavioural problems
  • Typically swallowed, snorted, smoked or injected
  • Even months after stopping regular use a single moderate dose of stimulant can lead to rapid return of abnormal behaviour patterns

Effects of amphetamines/stimulants

  • Decreased sleep
  • Elevated mood, confidence, energy, sex drive
  • Can cause preterm labour, miscarriage, damage to unborn baby
  • If used close to birth — baby may be unsettled, irritable, withdrawal symptoms in first few weeks, can be hard to feed — can be transferred through breastmilk
  • Can cause acute psychosis — see Mental health emergency

Can cause potentially life-threatening serotonin syndrome, particularly if person also takes other medicines that increase serotonin, eg antidepressants

Intoxication

  • Over confident, talking loudly and/or fast, restless, excited, agitated, aggressive, pacing, repetitive acts, panic states, not hungry/eating, may not have slept
  • High Temp, fast and/or irregular pulse, high BP, disturbed BGL
  • Pupils dilated and sluggish reaction to light
  • Fits, delirium, unconscious

Acute psychosis

  • Symptoms usually stop soon after drug use stops, but can have symptoms for weeks or months — see Psychosis

Chronic toxicity

  • Skin sores and scabs from scratching 
  • Muscle and limb twitches, increased ‘startle’ responses
  • Weight loss — due to poor appetite, poor nutrition, social circumstances
  • Poor concentration and attention, memory loss, anxiety, panic attacks, hallucinations, flashbacks
  • Social isolation

Management of stimulant withdrawal

  • Withdrawal usually takes 7–15 days
  • Withdrawal depression can lead to thoughts of suicide, self-harm

Table 5.6   Stimulant withdrawal

Ask

If person unable to respond — ask family or friends

  • What have they taken and how — smoking, tablets, injection
  • When did they have it last — day/date and time
  • How often and how much used
  • Does anyone think using it has caused the person harm
  • Other drugs used — prescribed, legal, illegal
  • Existing mental illness
  • Thoughts of self-harm or suicide

Check

  • Calculate age-appropriate REWS
    • Adult — AVPU, RR, O2 sats, pulse, BP, Temp
    • Child (less than 13 years) — AVPU, respiratory distress, RR, O2 sats, pulse, central capillary refill time, Temp
  • Weight, BGL
  • U/A — positive blood may mean muscle break down
  • Urine drug screen if drug use unclear — results may take weeks. Still important for long term management
  • Coma scale score, pupil size
    • Head-to-toe exam — with attention to hydration, head injury, infection from IV drug use (eg endocarditis, encephalitis)

Do

  • Medical consult
    • If marked agitation, insomnia, aggression — give diazepam oral — adult 10mg hourly up to 40mg/day until sedation score 1 (a bit sleepy but easy to rouse) 
    • If psychotic features — give olanzapine oral — adult 5–10mg/dose up to 20mg/day
  • Use calming techniques
  • Maintain nutritional status, fluid balance
  • If BGL less than 4mmol/L — see Hypoglycaemia

Follow-up