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Ecstasy
Ecstasy
(methylenedioxymethamfetamine,
MDMA)
may cause severe reactions,
even at
doses
that were previously tolerated. The most serious effects
are delirium,
coma,
convulsions,
ventricular
arrhyth-
mias, hyperthermia, rhabdomyolysis, acute renal failure,
acute hepatitis,
disseminated intravascular coagulation,
adult
respiratory
distress
syndrome,
hyperreflexia,
hypotension and intracerebral
haemorrhage;
hyponatr-
aemia has also been associated with ecstasy use.
Treatment of
methylenedioxymethamfetamine poison-
ing is
supportive,
with diazepam to control
severe
agitation or persistent convulsions and close monitoring
including ECG.
Self-induced water intoxication should
be considered in patients with ecstasy poisoning.
‘Liquid ecstasy’
is
a term used for
sodium oxybate
(gamma-hydroxybutyrate,
GHB),
which is a sedative.
Theophylline
Theophylline and related drugs are often prescribed as
modified-release formulations and toxicity can therefore
be delayed. They cause vomiting (which may be severe
and intractable),
agitation,
restlessness,
dilated pupils,
sinus tachycardia,
and hyperglycaemia.
More serious
effects are haematemesis,
convulsions,
and supraven-
tricular
and ventricular
arrhythmias.
Severe hypokal-
aemia may develop rapidly.
Repeated doses of
activated charcoal
can be used to
eliminate theophylline even if
more than 1 hour
has
elapsed after
ingestion and especially if
a modified-
release preparation has
been taken (see also under
Active
Elimination Techniques,
p.
33).
Ondansetron
(section 4.6) may be effective for severe vomiting that
is resistant to other antiemetics [unlicensed indication].
Hypokalaemia is corrected by intravenous infusion of
potassium chloride and may be so severe as to require
60 mmol/hour
(high doses require ECG monitoring).
Convulsions should be controlled by intravenous admin-
istration of
lorazepam or diazepam (see Convulsions,
p.
33).
Sedation with diazepam may be necessary in
agitated patients.
Provided the patient
does not
suffer
from asthma,
a
short-acting beta-blocker (section 2.4) can be adminis-
tered intravenously to reverse severe tachycardia, hypo-
kalaemia,
and hyperglycaemia.
Other poisons
Consult either the National Poisons Information Service
day and night or TOXBASE, see p.
32.
The National
Poisons Information Service (Tel:
0844 892 0111) will provide specialist advice on all
aspects of poisoning day and night
Cyanides
Oxygen should be administered to patients with cya-
nide poisoning.
The choice of antidote depends on the
severity of
poisoning,
certainty of
diagnosis,
and the
cause.
Dicobalt edetate is the antidote of choice when
there is a strong clinical
suspicion of
severe cyanide
poisoning.
Dicobalt
edetate itself
is toxic,
associated
with anaphylactoid reactions,
and is potentially fatal
if
administered in the absence of
cyanide poisoning.
A
regimen of sodium nitrite followed by sodium thiosul-
phate is an alternative if
dicobalt edetate is not avail-
able.
Hydroxocobalamin (
Cyanokit
c
—no other preparation
of hydroxocobalamin is suitable) can be considered for
use in victims of
smoke inhalation who show signs of
significant cyanide poisoning.
DICOBALT EDETATE
Indications
severe poisoning with cyanides
Cautions
owing to toxicity to be used only for definite
cyanide poisoning when patient tending to lose, or has
lost, consciousness; not to be used as a precautionary
measure
Side-effects
hypotension, tachycardia, and vomiting;
anaphylactoid reactions including facial and laryngeal
oedema and cardiac abnormalities
Dose
. By intravenous injection,
ADULT
300 mg over 1 minute
(5 minutes if condition less serious) followed imme-
diately by 50 mL of glucose intravenous infusion 50%;
if response inadequate a second dose of both may be
given, but risk of cobalt toxicity;
CHILD
consult the
National Poisons Information Service
1
Dicobalt Edetate
(Non-proprietary) A
Injection
,
dicobalt edetate 15 mg/mL,
net price 20-
mL (300-mg) amp = £13.75
HYDROXOCOBALAMIN
Indications
see notes above
Side-effects
gastro-intestinal disturbances,
transient
hypertension,
peripheral oedema,
dyspnoea,
throat
disorders, hot flush, dizziness, headache, restlessness,
memory impairment,
red coloration of urine,
lym-
phocytopenia, eye disorders, pustular rashes, pruritus,
reversible red coloration of skin and mucous mem-
branes
Dose
. By intravenous infusion,
ADULT
5 g over 15 minutes; a
second dose of 5 g can be given over 15 minutes–2
hours depending on severity of poisoning and patient
stability;
CHILD
70 mg/kg (max. 5 g) over 15 minutes; a
second dose of 70 mg/kg (max. 5 g) can be given over
15 minutes–2 hours depending on severity of pois-
oning and patient stability
Cyanokit
c
(Swedish Orphan) T A
Intravenous infusion
,
powder for reconstitution,
hydroxocobalamin, net price 2 2.5-g vials = £772.00
Note
Deep red colour of
hydroxocobalamin may interfere with
laboratory tests (see Side-effects, above)
SODIUM NITRITE
Indications
poisoning with cyanides (used in con-
junction with sodium thiosulphate)
Side-effects
flushing and headache due to vasodila-
tation
1.
A restriction does not apply where administration is for
saving life in emergency
BNF 61
Emergency treatment of poisoning
39
Emergency treatment of poisoning