Page 529 - Medicine and Surgery

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Chapter 15: Alcohol and drugs of abuse 525

Pathophysiology 1 Seizures and agitation are treated with diazepam or
Amphetamines are stimulant drugs with cardiovascular, lorazepam.
neuropsychiatric and other physiological effects. Multi- 2 Hypertension should be treated with diazepam or
ple doses, taken to maintain euphoria, can lead to intox- if this is ineffective, intravenous glyceryl trinitrate
ication, and feelings of anxiety and paranoia. Tolerance (GTN).
to amphetamines can take place with increased doses or 3 Hypovolaemia should be treated with fluid resuscita-
a different method of administration, e.g. smoking or tion, consider inotropes, and treat metabolic acidosis
injecting rather than oral. In psychological dependence with sodium bicarbonate as necessary.
withdrawal can cause depression, profound lethargy and 4 Cardiac arrhythmias or refractory hypertension re-
hunger. Street amphetamine usually only contains ∼5% quire specialist advice, for example from the NPIS.
of the drug, mixed with other substances including baby 5 Amphetamine abusers should be offered drug reha-
milk powder, lead, caffeine and paracetamol or codeine. bilitation counselling.
This makes it particularly dangerous to inject. The excre-
tion of amphetamine depends on urine pH – acid urine
increases its clearance. Ecstasy abuse
Definition
Clinical features Ecstasy is a semi-synthetic derivative of amphetamine
Physical effects of an amphetamine-intoxicated state in- with hallucinogenic properties. Its full name is 3,4-
clude tachypnoea, tachycardia, decreased appetite and methylenedioxymethamphetamine (MDMA). Ecstasy
increased motor activity. A history should be taken of re- usually comes in tablets or capsules, which may have
centandpreviousrecreationaldruguse,includingmeth- logos or pictures on them. Street names include ‘doves,
ods of administration, and alcohol intake. A psychiatric E, M and Ms, sweeties, X, brownies’. Occasionally it is
and social history should be taken, as well as a medical found in a powder form that is smoked or snorted.
history and examination.
Incidence/prevalence
Complications Ecstasy use continues to rise, doubling in the last 5
Medical complications include seizures, coma, tach- years. Now 2.2% of the population aged 16–59 years take
yarrhythmias, hyperthermia and hypertension. Acute ecstasy, with rates approaching 30% in university stu-
hepatic failure has been reported. Psychiatric complica- dents. There have been over 200 deaths from the drug in
tions include paranoia, eating disorders, hallucinations 15 years.
and panic attacks. Loss of judgement, e.g. when car driv-
ing or a bad trip can lead individuals to become un- Pathophysiology
characteristically aggressive and violent, causing harm MDMA causes the release of serotonin and dopamine in
to themselves or others. thebrain,andbothcentralandperipheralcatecholamine
release. The pills can contain from 30 to 300 mg of
Investigations MDMA, and in some cases the drug is replaced or mixed
If the individual is euphoric, but with no physical side- with other substances such as amphetamine, caffeine or
effects, there is no need for specific investigations and toxicsubstances.Theeffectsoftakingadosearetherefore
should be monitored for 4 hours. If physical side-effects highly variable, but in addition idiosyncratic responses
are present, U&Es, liver function tests, creatine kinase appear to occur, both in na¨ ıve and chronic users.
and an ECG should be performed. The core temperature
should be checked. Clinical features
Effects begin within an hour and usually last 4–6

Management hours, but may persist for 48 hours with very high
In more than mild toxicity, patients should have cardiac doses. Common physical effects include tachycar-
monitoring. dia, mild hypertension, dry mouth, reduced appetite,