New Zealand Autism Spectrum Disorder Guideline - Ministry of Health

Part 4: Treatment and management of ASD
Part 4
New Zealand. Use of any of these agents to treat
children with ASD in New Zealand would be
off-label and would be regarded as out of line
with current standard practice in this country.
None of these agents is recommended.
Amantadine
Amantadine (Symmetrel) is a non-competitive
N-methyl-d-aspartate (NMDA) receptor
antagonist licensed in New Zealand for use as
an antiviral agent and as an antiparkinsonian
agent. One randomised controlled study was
identified 325 . This study found statistically
significant improvement on some subscales
(notably hyperactivity) on investigator
ratings, but no differences on parent ratings
(Recommendation 4.2.11).
Immunoglobulins
One small double-blind placebo‐controlled study
on the use of intravenous immunoglobulins was
reported in a letter to a journal but is difficult to
evaluate 326 . The authors reported improvement
on parent and teacher ratings but no difference
on clinician ratings. They urged caution and
recommended further research (Recommendation
4.2.11).
Naltrexone
Naltrexone is an opioid antagonist. It is used in
New Zealand in the management of opioid and
alcohol dependence. It has largely been used in
relation to repetitive self-injury in children and
adolescents with ASD.
As with other agents, there are several case
reports and open-label studies. Two doubleblind
placebo-controlled crossover studies,
with very small numbers of children, were
identified 327 328 . Results were inconsistent with
improvement in teacher ratings (but not in
parent ratings) achieving statistical significance
in one study and the opposite finding in the
other study (Recommendation 4.2.11).
Fenfluramine
Fenfluramine (Ponderax) was previously
available in New Zealand for use as an anorectic
in obesity. It has been withdrawn because
of concerns about safety. In the early 1980s
there was substantial interest in the use of
fenfluramine in ASD. Fenfluramine significantly
lowers blood serotonin levels, which are
elevated in a proportion of individuals with
ASD (and other developmental disorders). A
non-systematic review concluded that, while
there were many studies of this agent, there were
some concerns about methodology, even in some
trials described as double-blind and placebocontrolled
329 . A double-blind placebo-controlled
trial was also identified 330 . While there are some
data to suggest that fenfluramine enhances
social relatedness and reduces stereotypies and
overactivity, the results are not consistent. There
have been significant concerns about potential
neurotoxicity on the basis of animal studies as
well as reports of significant adverse effects in
humans and depletion of brain serotonin with
long-term use (Recommendation 4.2.12).
Secretin
There is no evidence to support the use of
secretin (either human, synthetic or porcine)
in children with ASD. There was an initial
surge of enthusiasm over this medication in the
1990s, following a report that three children,
who received secretin while undergoing
gastroenterological investigations, had
demonstrated improvement in their autistic
symptomatology following infusion. Subsequent
anecdotal reports and open-label studies
appeared to confirm that secretin might be
effective. There have now been several doubleblind
randomised controlled trials, all of which
have demonstrated that secretin is ineffective 331
332
(Recommendation 4.2.12).
Chelation therapy
There is no evidence that heavy metals are
implicated in the causation of ASD. There are
no randomised controlled trials of chelation
therapy in children with ASD. Chelation therapy
is potentially dangerous and, given the absence
of evidence for benefit, should not be used 333
(Recommendation 4.2.12).
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New Zealand Autism Spectrum Disorder Guideline