No trials reported serious adverse events .
Subgroup analysis by dose did not identify any significant differences in effect on our primary outcomes between low- , medium- or high-dose ranges .
We found that short-term use of methylpheni date might improve symptoms of hyperactivity and possibly inattention in children with ASD who are tolerant of the medication , although the low quality of evidence means that we can not be certain of the true magnitude of any effect .
There was no evidence that methylpheni date has a negative impact on the core symptoms of ASD , or that it improves social interaction , stereotypical behaviours , or overall ASD .
BACKGROUND Children with autistic spectrum disorder ( ASD ) frequently present with inattention , impulsivity and hyperactivity , which are the cardinal symptoms of attention deficit hyperactivity disorder ( ADHD ) .
The effectiveness of methylpheni date , a commonly used ADHD treatment , is therefore of interest in these children .
OBJECTIVES To assess the effects of methylpheni date for symptoms of ADHD ( inattention , impulsivity and hyperactivity ) and ASD ( impairments in social interaction and communication , and repetitive , restricted or stereotypical behaviours ) in children and adolescents aged 6 to 18 years with ASD .
Chelation for autism spectrum disorder (ASD).
BACKGROUND It has been suggested that the severity of autism spectrum disorder ( ASD ) symptoms is positively correlated with the level of circulating or stored toxic metals , and that excretion of these heavy metals , brought about by the use of pharmaceutical chelating agents , results in improved symptoms . OBJECTIVES To assess the potential benefits and adverse effects of pharmaceutical chelating agents ( referred to as chelation therapy throughout this review ) for autism spectrum disorder ( ASD ) symptoms . SEARCH METHODS We search ed the following data bases on 6 November 2014 : CENTRAL , Ovid MEDLINE , Ovid MEDLINE In-Process , Embase , PsycINFO , Cumulative Index to Nursing and Allied Health Literature ( CINAHL ) and 15 other data bases , including three trials registers . In addition we checked references lists and contacted experts . SELECTION CRITERIA All r and omised controlled trials of pharmaceutical chelating agents compared with placebo in individuals with ASD . DATA COLLECTION AND ANALYSIS Two review authors independently selected studies , assessed them for risk of bias and extracted relevant data . We did not conduct a meta- analysis , as only one study was included . MAIN RESULTS We excluded nine studies because they were non-r and omised trials or were withdrawn before enrolment . We included one study , which was conducted in two phases . During the first phase of the study , 77 children with ASD were r and omly assigned to receive seven days of glutathione lotion or placebo lotion , followed by three days of oral dimercaptosuccinic acid ( DMSA ) .  Forty-nine children who were found to be high excreters of heavy metals during phase one continued on to phase two to receive three days of oral DMSA or placebo followed by 11 days off , with the cycle repeated up to six times . The second phase thus assessed the effectiveness of multiple doses of oral DMSA compared with placebo in children who were high excreters of heavy metals and who received a three-day course of oral DMSA . Overall , no evidence suggests that multiple rounds of oral DMSA had an effect on ASD symptoms . AUTHORS ' CONCLUSIONS This review included data from only one study , which had method ological limitations . As such , no clinical trial evidence was found to suggest that pharmaceutical chelation is an effective intervention for ASD . Given prior reports of serious adverse events , such as hypocalcaemia , renal impairment and reported death , the risks of using chelation for ASD currently outweigh proven benefits . Before further trials are conducted , evidence that supports a causal link between heavy metals and autism and methods that ensure the safety of participants are needed
No trials reported serious adverse events .
Subgroup analysis by dose did not identify any significant differences in effect on our primary outcomes between low- , medium- or high-dose ranges .
We found that short-term use of methylpheni date might improve symptoms of hyperactivity and possibly inattention in children with ASD who are tolerant of the medication , although the low quality of evidence means that we can not be certain of the true magnitude of any effect .
There was no evidence that methylpheni date has a negative impact on the core symptoms of ASD , or that it improves social interaction , stereotypical behaviours , or overall ASD .
BACKGROUND Children with autistic spectrum disorder ( ASD ) frequently present with inattention , impulsivity and hyperactivity , which are the cardinal symptoms of attention deficit hyperactivity disorder ( ADHD ) .
The effectiveness of methylpheni date , a commonly used ADHD treatment , is therefore of interest in these children .
OBJECTIVES To assess the effects of methylpheni date for symptoms of ADHD ( inattention , impulsivity and hyperactivity ) and ASD ( impairments in social interaction and communication , and repetitive , restricted or stereotypical behaviours ) in children and adolescents aged 6 to 18 years with ASD .