Regarding the primary outcome of psychological and learning capabilities , both studies assessed the effect of interventions on  children 's verbal and non-verbal intellectual functioning using the Wechsler Intelligence Scale for Children - Revised .
AUTHORS ' CONCLUSIONS Low- quality evidence from two small trials showed that when compared to placebo , LAC may not improve intellectual functioning or hyperactive behaviour in children with FXS
BACKGROUND People with fragile X syndrome ( FXS ) have an intellectual dysfunction that can range from very mild to severe .
Symptoms can include speech and language delays and behavioural difficulties such as aggression or self injurious behaviours , emotional lability , and anxiety-related problems ( for example obsessive-compulsive symptoms and perseverative behaviours ) .
In some cases , affected people may have an additional diagnosis of attention deficit hyperactivity disorder or an autism spectrum disorder .
OBJECTIVES To review the efficacy and safety of L-acetylcarnitine in improving the psychological , intellectual , and social performance of people with FXS .
Acetyl-L-Carnitine as an Adjunctive Therapy in the Treatment of Attention-Deficit/Hyperactivity Disorder in Children and Adolescents: A Placebo-Controlled Trial
The objective of this study was to test whether a previous observed Acetyl-L-carnitine ( ALC ) treatment effect could be repeated in an ALC adjunctive therapy treatment trial of attention-deficit/hyperactivity disorder ( ADHD ) in children and adolescents . This was a six-week , r and omized clinical trial undertaken in an outpatient child and adolescent clinic . Subjects included 40 out patients ( 28 boys and 12 girls ) between the ages of 7–13 who met the DSM-IV-TR diagnostic criteria for ADHD . All study subjects were r and omly assigned to receive treatment using capsules of ALC doses ranging from 500 to 1,500 mg/day depending on the weight of the child plus methylpheni date at a dose of 20–30 mg/day depending on weight or Placebo plus methylpheni date at a dose of 20–30 mg/day depending on weight . The principal measure of outcome was the Teacher and Parent attention deficit/hyperactivity disorder Rating Scale- IV . No difference was observed between the two groups on the Parent and Teacher Rating Scale scores ( df = 1 ; F = 0.10 ; P = 0.74 and df = 1 ; F = 0.22 ; P = 0.63 respectively ) . Side effects consisting of headache and irritability were observed more frequently in the methylpheni date plus placebo group . The results of this study do not support the application of ALC as an adjunctive therapy to methylpheni date in children and adolescents with ADHD
Regarding the primary outcome of psychological and learning capabilities , both studies assessed the effect of interventions on  children 's verbal and non-verbal intellectual functioning using the Wechsler Intelligence Scale for Children - Revised .
AUTHORS ' CONCLUSIONS Low- quality evidence from two small trials showed that when compared to placebo , LAC may not improve intellectual functioning or hyperactive behaviour in children with FXS
BACKGROUND People with fragile X syndrome ( FXS ) have an intellectual dysfunction that can range from very mild to severe .
Symptoms can include speech and language delays and behavioural difficulties such as aggression or self injurious behaviours , emotional lability , and anxiety-related problems ( for example obsessive-compulsive symptoms and perseverative behaviours ) .
In some cases , affected people may have an additional diagnosis of attention deficit hyperactivity disorder or an autism spectrum disorder .
OBJECTIVES To review the efficacy and safety of L-acetylcarnitine in improving the psychological , intellectual , and social performance of people with FXS .