New Zealand Autism Spectrum Disorder Guideline - Ministry of Health

Part 4: Treatment and management of ASD
Part 4
therefore, many recommendations are based
on short-term studies or expert opinion.
Many medications utilised for children and
adolescents with ASD have been developed
for and tested in adults. Because of important
potential differences in pharmacokinetics
(metabolism etc) and pharmacodynamics
(effects on the body and mind), findings from
the adult literature should be applied to children
and adolescents with significant caution.
Studies involving children and adolescents
are slow to take place and numbers included
in studies small. Prescription of many agents
will, by necessity, therefore be ‘off-label’ when
applied to children with autism (that is, outside
manufacturers’ recommendations) 292 . Parents,
carers and professionals need to be aware of the
implications of this practice.
In addition, the response to medications used to
treat co-morbidities may be different for children
with ASD so that special care is needed when
prescribing in this group. For example, many
children with ASD have coexisting significant
ADHD symptomatology. While this may
often improve significantly with stimulants,
stimulants may increase anxiety and stereotyped
behaviour. Stimulants may therefore be less
useful in some children with autism. There is
evidence that suggests that some children with
ASD become over-focused when on stimulant
medication, and repetitive and obsessional
behaviour may be exacerbated 293 .
Clearly, for reasons of brevity, this review
cannot address the vast literature on the use of
psychoactive medications in disorders other
than ASD. This means that any prescriber
working with children with ASD must have
a good working knowledge of psychiatric
disorders, their diagnosis and treatment, and
indeed of all psychoactive drugs, including their
safety and efficacy. If the prescriber does not
have this knowledge, then access to a child and
adolescent psychiatrist or other appropriately
knowledgeable prescriber is necessary. Where
there is clear and properly diagnosed evidence
of another mental health disorder (eg, ADHD),
the child or person with ASD has should be
treated according to evidence-based treatment
guidelines for that disorder. However,
prescribers must make it clear that the treatment
may not improve ASD symptoms, and must
ensure that there is monitoring for side effects
(including worsening of ASD core symptoms
like obsessional anxiety).
Some medications currently in use in children
with ASD in New Zealand are relatively new
medications. It is essential that both clinicians
and parents appreciate that there is therefore
very limited information on long-term safety.
As children with challenging behaviour
may remain on these medications for many
years, both prescribers and parents need to
understand that there is an element of risk in
the use of such drugs.
The therapeutic use of a large number of
different medications and other approaches such
as biological agents and dietary approaches (see
section 4.5 Other interventions) has been studied
in ASD and related disorders, but not many
are supported by rigorous evidence. Some
of the studies have only assessed classes of
medications, rather than individual agents. The
most commonly studied agents are risperidone,
fenfluramine, secretin and naltrexone. Some
of the evidence for medications may be biased
because the studies have been funded by the
manufacturers. Medications for which little or
no evidence base exists are not necessarily less
effective, but it is recommended that clinicians
avoid using medications for which evidence of
efficacy is not available.
A useful summary of issues in paediatric
psychopharmacological prescribing may be
found in a number of reviews by experts,
although only the first of these is autism
specific 294-296 .
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New Zealand Autism Spectrum Disorder Guideline