Attention Deficit Disorders, Narcolepsy: Attention Deficit Disorders (previously known as Minimal Brain Dysfunction in Children).
Other terms being used to describe the behavioral syndrome below include: Hyperkinetic Child Syndrome, Minimal Brain Damage, Minimal Cerebral Dysfunction, Minor Cerebral Dysfunction.Methylphenidate hydrochloride is indicated as an integral part of a total treatment program which typically includes other remedial measures (psychological, educational, social) for a stabilizing effect in children with a behavioral syndrome characterized by the following group of developmentally inappropriate symptoms: moderate-to-severe distractibility, short attention span, hyperactivity, emotional lability, and impulsivity.
The diagnosis of this syndrome should not be made with finality when these symptoms are only of comparatively recent origin.
Nonlocalizing (soft) neurological signs, learning disability, and abnormal EEG may or may not be present, and a diagnosis of central nervous system dysfunction may or may not be warranted.Special Diagnostic Considerations: Specific etiology of this syndrome is unknown, and there is no single diagnostic test.
Adequate diagnosis requires the use not only of medical but of special psychological, educational, and social resources.Characteristics commonly reported include: chronic history of short attention span, distractibility, emotional lability, impulsivity, and moderate-to-severe hyperactivity; minor neurological signs and abnormal EEG.
Learning may or may not be impaired.
The diagnosis must be based upon a complete history and evaluation of the child and not solely on the presence of one or more of these characteristics.Drug treatment is not indicated for all children with this syndrome.
Stimulants are not intended for use in the child who exhibits symptoms secondary to environmental factors and/or primary psychiatric disorders, including psychosis.
Appropriate educational placement is essential and psychosocial intervention is generally necessary.When remedial measures alone are insufficient, the decision to prescribe stimulant medication will depend upon the physician’s assessment of the chronicity and severity of the child’s symptoms.
Marked anxiety, tension, and agitation are contraindications to methylphenidate hydrochloride, since the drug may aggravate these symptoms.Methylphenidate is contraindicated also in patients known to be hypersensitive to the drug, in patients with glaucoma, and in patients with motor tics or with a family history or diagnosis of Tourette’s syndrome.Methylphenidate is contraindicated during treatment with monoamine oxidase inhibitors, and also within a minimum of 14 days following discontinuation of a monoamine oxidase inhibitor (hypertensive crises may result).
Methylphenidate should not be used in children under six years, since safety and efficacy in this age group have not been established.Sufficient data on safety and efficacy of long-term use of methylphenidate in children are not yet available.
Although a causal relationship has not been established, suppression of growth (i.e., weight gain and/or height) has been reported with the long-term use of stimulants in children.
Therefore, patients requiring long-term therapy should be carefully monitored.Methylphenidate should not be used for severe depression of either exogenous or endogenous origin.
Clinical experience suggests that in psychotic children, administration of methylphenidate may exacerbate symptoms of behavior disturbance and thought disorder.Methylphenidate should not be used for the prevention or treatment of normal fatigue states.There is some clinical evidence that methylphenidate may lower the convulsive threshold in patients with prior history of seizures, with prior EEG abnormalities in absence of seizures, and, very rarely, in absence of history of seizures and no prior EEG evidence of seizures.
Safe concomitant use of anticonvulsants and methylphenidate has not been established.
In the presence of seizures, the drug should be discontinued.Use cautiously in patients with hypertension.
Blood pressure should be monitored at appropriate intervals in all patients taking methylphenidate, especially those with hypertension.Symptoms of visual disturbances have been encountered in rare cases.
Difficulties with accommodation and blurring of vision have been reported.Drug Interactions: Methylphenidate may decrease the hypotensive effect of guanethidine.
Use cautiously with pressor agents and MAO inhibitors.Human pharmacologic studies have shown that methylphenidate may inhibit the metabolism of coumarin anticoagulants, anticonvulsants (phenobarbital, phenytoin, primidone), phenylbutazone, and tricyclic antidepressants (imipramine, clomipramine, desipramine).
Downward dosage adjustments of these drugs may be required when given concomitantly with methylphenidate.Serious adverse events have been reported in concomitant use with clonidine, although no causality for the combination has been established.
The safety of using methylphenidate in combination with clonidine or other centrally acting alpha-2 agonists has not been systemically evaluated.Usage in Pregnancy: Adequate animal reproduction studies to establish safe use of methylphenidate during pregnancy have not been conducted.
However, in a recently conducted study, methylphenidate has been shown to have teratogenic effects in rabbits when given in doses of 200 mg/kg/day, which is approximately 167 times and 78 times the maximum recommended human dose on a mg/kg and a mg/m2 basis, respectively.
In rats, teratogenic effects were not seen when the drug was given in doses of 75 mg/kg/day, which is approximately 62.5 and 13.5 times the maximum recommended human dose on a mg/kg and a mg/m2 basis, respectively.
Therefore, until more information is available, methylphenidate should not be prescribed for women of childbearing age unless, in the opinion of the physician, the potential benefits outweigh the possible risks. Drug Dependence: Methylphenidate should be given cautiously to emotionally unstable patients, such as those with a history of drug dependence or alcoholism, because such patients may increase dosage on their own initiative. Chronically abusive use can lead to marked tolerance and psychic dependence with varying degrees of abnormal behavior.
Frank psychotic episodes can occur, especially with parenteral abuse.
Careful supervision is required during drug withdrawal, since severe depression as well as the effects of chronic overactivity can be unmasked.Long-term follow-up may be required because of the patient’s basic personality disturbances.