Page 527 - Medicine and Surgery

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Chapter 15: Alcohol and drugs of abuse 523

water used to mix the powder lead to cellulitis, throm- Cocaine abuse and dependence
bophlebitis, skin and organ (e.g. cerebral) abscesses
Definition
and infective endocarditis. Sharing of needles means
Cocaine abuse is defined as the continued use of
that hepatitis B and C, and HIV can be transmitted.
cocaine/crack despite it causing significant problems,
Deep vein thromboses and pulmonary emboli occur.
which may be social, neuropsychiatric or physical.
Other problems include acute pulmonary oedema,
Cocaine hydrochloride (HCl) is made from the leaves
anaphylaxis and aspiration pneumonia.
ofthecocashrub.Itisnormallyboughtasawhitepowder,
Withexcessivedoses,comaanddeathfromrespiratory

which is usually snorted or smoked. Freebasing is where
failure occur. The variability in the purity of street
cocaine HCl (the salt) is dissolved in water and heated
heroin means that with every use there is a risk of
with baking soda, ether or ammonia to free the cocaine
accidental overdose, especially after a break from use
alkaloid base. This combusts more readily making the
when tolerance is reduced, or if other drugs or alcohol
cocaine more potent. Crack is a form of freebase cocaine
increase the sedative effect.
made by using baking soda, which looks like little lumps
Withdrawal leads to nausea, vomiting, abdominal

(‘rocks’) and makes a crackling sound when burnt.
cramps, diarrhoea, watery eyes and nose and muscle
Street names for cocaine include ‘C, charlie, coke, dust
twitching. Seizures may occur.
andwhite’,andforcrackinclude‘base,freebaseandrock’.
Social problems include loss of job, deterioration in

The street term ‘freebasing’ means smoking cocaine, ei-
relationships and criminal activities to obtain money
ther as the salt or base. Cocaine and crack can also be
tobuydrugs,includingstealing,prostitutionanddrug
injected, although this is far less common.
dealing.
Incidence/prevalence
Investigations
7% of 20–24 year olds have tried cocaine, mainly snort-
These depend on the presentation of the individual. In-
ing. About 10–15% of those who try snorting cocaine
vestigations may be needed for possible complications
become abusers. Crack is less commonly used, but ad-
such as infective endocarditis, HIV, hepatitis and DVT,
diction occurs faster. Crack is linked with areas of social
depending on the history and clinical diagnosis.
deprivation, whereas cocaine HCl tends to be associated
with an expensive lifestyle. Cocaine HCl and crack abuse
Management
is rising.
Heroin intoxication is treated by ensuring airway pro-
tection, and giving the opiate antagonist naloxone. This Pathophysiology
rapidly reverses the opiate action, but is short-acting, so Cocaine HCl and crack are strong, short-acting stimu-
the patient requires further monitoring for 24 hours and lant drugs. They are not physically addictive in the same
may need a naloxone infusion. wayasopiates,butcocaineaddictswillcompulsivelytake
Heroin abusers should be referred to a drug rehabil- doses in a ‘binge’ in order to keep experiencing the highs
itation counsellor or centre, and considered for reha- and to avoid the depression and fatigue that occur when
bilitation. Methadone, a long-acting opiate, which does the drug wears off. Tolerance does seem to occur to some
not cause euphoria, is used as a method of programmed extent. Snorting cocaine HCl leads to effects within min-
withdrawal, to ameliorate the withdrawal symptoms. utes,whichlastabouthalfanhour.Baseformsofcocaine,
Supportive therapy is needed to prevent the patient from including crack, have a more rapid onset but a much
seeking increased doses (either of heroin, other drugs or shorter duration of action. When cocaine is taken with
even methadone) elsewhere, and relapse is common. In alcohol, its effects are increased by an active metabolite,
some cases, patients stay on long-term methadone at which only forms in the presence of alcohol.
alow maintenance dose. Although they remain depen-
dant on methadone, they are less likely to relapse, less Clinical features
likely to have an overdose, and are not at risk from HIV After taking cocaine, the user feels intense euphoria.
infection. Physical side effects include dilated pupils, dry mouth,