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522 Chapter 15: Overdose, poisoning and addiction

Investigations junk, skag, white stuff, sugar’. Health care professionals
Blood alcohol levels are of limited value, a persistently with access to opiates may abuse drugs like fentanyl.
raised MCV or γGT are suggestive of continued alcohol
use. Incidence/prevalence
Heroin abuse fell during the late 1990s, but rose again
rapidly in 2000 and 2001. A fall in use since then has
Management
been attributed to the fall in supply after the Taliban
1 Identification and advice at an early stage may be
enough to avert serious medical, neuropsychiatric banned production in Afghanistan. Despite the fall in
and social consequences of alcohol. Precipitating fac- numbers of users, the number of heroin-induced deaths
tors should be identified and psychological sup- has remained static. Heroin and morphine account
port/therapy instituted as appropriate. for ∼40% of drug-abuse-related deaths in the United
2 Abstinence, individuals may require general sup- Kingdom.
port (rehydration, correction of electrolyte imbal-
ance, complex intravenous vitamin preparations) and Pathophysiology
treatment to avoid specific complications, e.g. chlor- Opiates have central nervous system depressant effects,
diazepoxide in the treatment of delirium tremens and they act as analgesics and cause euphoria. Abusers
and diazepam or lorazepam in the treatment of repeatedly take the drug to achieve the euphoric effect;
seizures. however, this results in opiate tolerance, i.e. increased
3 Disulfiram (Antabuse) blocks metabolism resulting dosesarerequiredtoachievethesameeffect.Withdrawal
in acetaldehyde accumulation resulting in flushing, symptoms also occur, and so further doses are taken to
headache, anxiety and nausea. This may be implanted avoid the withdrawal.
to give6months of treatment. Heroincanbesmoked(‘chasingthedragon’),snorted,
or injected into a vein (‘shooting up’ or ‘mainlining’),
or subcutaneously (‘skin popping’) or intramuscularly.
Prognosis
It acts rapidly, within 10–20 seconds, if injected, and
15% die by suicide, 30% continue to have life-long
within 20–30 seconds, if snorted. Snorting is the most
alcohol-related problems.
commonmethodofuse,asitdoesnotrequireanyspecial
preparation. The effects last 4–6 hours.
Opiate abuse and dependence
Clinical features
Definition Following use of heroin, side effects include nausea and
Opiate dependence or addiction is defined as the con- vomiting (usually only on first few uses), drowsiness,
tinued use of opiates, despite these causing significant sedation, constricted pupils and dry, itchy skin.
problems, which may be physical, neuropsychiatric and Long-term users generally have constipation, features
social. of self-neglect, weight loss, there may be needle-tracks
Opiates are all drugs derived from opium, i.e. the milk and evidence of complications.
of the opium poppy. Opium contains morphine and A history should be taken of recent and previous
codeine. Natural and synthetic derivatives of these drugs heroin use, including methods of administration, use of
are useful, effective analgesics, but opiates also have the otherdrugssuchasbenzodiazepines,alcoholintake,pre-
potential to become drugs of abuse. vious attempted rehabilitation and any previous heroin-
Heroin (a derivative of morphine) is a popular opiate related problems. A close social history should be taken,
ofabuse,butotherdrugsincludingmorphine,pethidine, as well as a medical history and examination.
codeine and dihydrocodeine are also commonly abused.
In its pure form, heroin is a white powder, but on the Complications
streets it is bought as an off-white or brown powder, and The most serious complications are associated with
isknownbymanystreetnamesincluding‘H,gear,smack, intravenous use. Use of non-sterile equipment and