eMedicine Specialties > Neurology > Pediatric Neurology
Mental Retardation: Treatment & Medication
Updated: Apr 17, 2006
- Overview
- Differential Diagnoses & Workup
- Treatment & Medication
- Follow-up
Treatment
Medical Care
- The mainstay of treatment of MR is developing a comprehensive management plan for the condition. The complex habilitation plan for the individual requires input from care providers from multiple disciplines, including special educators, language therapists, behavioral therapists, occupational therapists, and community services that provide social support and respite care for families affected by MR.
- No treatments are available specifically for cognitive deficiency. Although the pharmacologic enhancement of cognition is an area of interest, research on such nootropic (ie, knowledge-enhancing) compounds is limited. Such drugs have not become part of the routine or even experimental clinical management of this population.
Consultations
- Ophthalmology
- Genetic evaluation, testing, and counseling
Diet
Nutritional supplements are of no proven benefit.
Medication
No specific pharmacologic treatment is available for cognitive impairment in the developing child or adult with MR. Medications, when prescribed, are targeted to specific comorbid psychiatric disease or behavioral disturbances.
Development of nootropic drugs that may alter cognitive processes positively has been of interest to researchers. Medications currently prescribed for dementia, such as acetylcholinesterase inhibitors, are not accepted treatments for MR, although clinical trials have not been conducted in children. Phosphodiesterase inhibitors enhance cortical plasticity in an animal model of fetal alcohol syndrome.
Although vitamin and mineral therapies have gained popularity, their efficacy has not been established in clinical trials. The use of antioxidant supplements in patients with Down syndrome is of theoretical benefit but has not yet been tested vigorously.
CNS stimulants
The most common class of drugs prescribed in this population is the psychostimulants because of the coexistence of attention deficit with or without hyperactivity disorder (ADHD/ADD) in as many as 50%. The most widely used psychostimulants are methylphenidate and dextroamphetamine, which appear to enhance dopamine and norepinephrine activity in the CNS.
Methylphenidate hydrochloride (Ritalin, Metadate ER)
Stimulates cerebral cortex and subcortical structures.
Adult
Pediatric
Dosages vary widely with no optimal dose schedule established
Recommended: 5 mg PO qd to start, titrate to tid or sustained release preparation; no known benefit of doses >60-70 mg/d
Reduces effects of guanethidine and bretylium; may increase toxicity of phenytoin, TCAs, warfarin, primidone, and phenobarbital; MAOIs increase toxicity
Documented hypersensitivity; marked anxiety and agitation; glaucoma; motor tics
Because of mild sympathomimetic cardiac effects, should be used with caution in children with congenital cardiac disease or hypertension
Pregnancy
C - Safety for use during pregnancy has not been established.
Precautions
Most common adverse effects are insomnia and anorexia; other adverse effects include headaches, stomachache, irritability, anxiety; "overly quiet" periods may limit titration to higher doses
Dextroamphetamine sulfate (Dexedrine) and racemic amphetamine (Adderall)
Increase amount of circulating dopamine and norepinephrine in cerebral cortex by blocking reuptake of norepinephrine or dopamine from synapse.
Adult
Pediatric
5 mg/d PO initially and titrate to tid; no benefit to doses >30-40 mg/d; required doses may actually be less in child with MR
MAOIs may precipitate hypertensive crisis and, with anesthetics, may precipitate arrhythmias; may increase toxicity of phenobarbital, propoxyphene, meperidine, TCAs, phenytoin, and norepinephrine
Documented hypersensitivity; hypertension; MAOIs; advanced arteriosclerosis; hyperthyroidism; glaucoma
Pregnancy
C - Safety for use during pregnancy has not been established.
Precautions
Caution in angina, glaucoma, cardiovascular disease, and psychopathic personalities
Antidepressants
These agents may be used when ADHD is comorbid with depression.
Bupropion (Wellbutrin, Zyban)
Aminoketone that primarily blocks neuronal dopamine uptake and is modestly effective for ADHD symptoms.
Adult
Pediatric
Not established; 75 mg PO qd to start and titrate up to 300 mg/d divided tid; long-acting preparations are available
Carbamazepine, cimetidine, phenytoin, and phenobarbital may decrease effects; levodopa and MAOIs increase toxicity
Documented hypersensitivity; seizure disorder; anorexia nervosa; concurrent MAOIs
Pregnancy
B - Usually safe but benefits must outweigh the risks.
Precautions
Slightly increased rate of seizures (0.4%); few adverse cardiovascular effects; adverse effects include agitation, insomnia, psychosis, and anorexia; efficacy may not be apparent before 4 wk of therapy
Alpha-adrenergic agonists
These agents are used commonly to modulate hyperactivity, aggression, tics, and dyssomnias.
Clonidine hydrochloride (Catapres)
Agonist at presynaptic alpha2-adrenergic receptors within brain stem. Clonidine reduces norepinephrine release at these sites, reducing sympathetic outflow and enhancing parasympathetic outflow. May reduce aggression by increasing release of GABA in frontal cortex and other brain regions.
Adult
Pediatric
ADHD and Tourette disorder: 3-6 mcg/kg/d PO qhs or divided qid; initial dose typically 0.05 mg PO qhs; transdermal patches are available, although contact dermatitis reported in as many as 40%
Sedating drugs may cause untoward CNS depression; carbamazepine, cimetidine, phenytoin, and phenobarbital may decrease effects; levodopa and MAOIs may increase toxicity
Documented hypersensitivity; conduction disturbances; chronic renal failure; seizure disorder; anorexia nervosa; concurrent MAOIs
Pregnancy
C - Safety for use during pregnancy has not been established.
Precautions
Adverse effects include sedation, dry mouth, constipation, dizziness, fatigue, syncope, and dysrhythmias; must be tapered to discontinue over several days and never stopped abruptly
Guanfacine (Tenex)
Presynaptic alpha2-adrenergic receptor agonist that stimulates alpha2-adrenergic receptors in brain stem, activating an inhibitory neuron, which in turn decreases vasomotor tone and heart rate. Similar reduction in potentially negative impact on academic performance and cognitive function.
Adult
Pediatric
Not established; usually prescribed as 0.5-1 mg PO qhs and titrated to bid/tid
Increases effect of other hypotensive agents; TCAs may decrease hypotensive effects
Documented hypersensitivity
Pregnancy
B - Usually safe but benefits must outweigh the risks.
Precautions
Caution in hepatic impairment, severe coronary insufficiency, recent myocardial infarction
Neuroleptic drugs (antipsychotics)
The neuroleptic drugs are the most frequently prescribed agents for aggression, self-injury, and hyperactivity in people with MR. Increasingly, they are more likely to be reserved for the older child or adult in whom intensive behavioral intervention has failed. Likewise, the prevalence of comorbid psychiatric disorders in MR increases with age. Neuroleptics interact with receptors for a variety of brain neurotransmitters, including dopamine, serotonin, acetylcholine, histamine, and norepinephrine. Their ability to antagonize dopamine receptors appears to correlate well with the efficacy of these drugs and imparts their antipsychotic properties. Likewise, antidopaminergic activity evokes extrapyramidal symptoms. Rarely, neuroleptic malignant syndrome may occur.
Risperidone (Risperdal)
Atypical antipsychotic with fewer adverse neurologic effects and less propensity for extrapyramidal movements (eg, pseudoparkinsonism, akathisia, acute dystonias, tardive dyskinesia).
Adult
Pediatric
Not well established; titrate from initial dose of 0.5 mg PO bid
Carbamazepine may decrease effects; may inhibit effects of levodopa; clozapine may increase levels
Documented hypersensitivity
Pregnancy
C - Safety for use during pregnancy has not been established.
Precautions
Adverse effects include sedation, orthostatic hypotension, dysphagia, hyperprolactinemia, hyperkinesia, nausea, impaired learning, extrapyramidal movements; upon discontinuation, "withdrawal" disorder may occur and is not always prevented by slow taper
Haloperidol (Haldol)
DOC for acute psychosis when no contraindications. Haloperidol and droperidol are of butyrophenone class and are noted for high potency and low potential for causing orthostasis. Downside is high potential for EPS/dystonia.
Adult
Pediatric
0.5-6 mg/d total; titration can begin as 0.5 mg PO qd; increase by 0.5 mg PO q5-7d; not to exceed 0.15 mg/kg/d or 6 mg/d PO divided bid/tid
May increase TCA serum concentrations and hypotensive action of antihypertensive agents; phenobarbital or carbamazepine may decrease effects; anticholinergics may increase intraocular pressure; lithium may cause encephalopathy-like syndrome
Documented hypersensitivity; narrow-angle glaucoma; bone marrow suppression; severe cardiac or liver disease; severe hypotension; subcortical brain damage
Pregnancy
C - Safety for use during pregnancy has not been established.
Precautions
Severe neurotoxicity manifesting as rigidity or inability to walk or talk may occur in patients with thyrotoxicosis also receiving antipsychotics; if IV/IM, watch for hypotension; caution in diagnosed CNS depression or cardiac disease; if history of seizures, benefits must outweigh risks; significant increase in body temperature may indicate intolerance to antipsychotics (discontinue drug if it occurs)
Aripiprazole (Abilify)
A newer atypical antipsychotic, aripiprazole is indicated in acute bipolar mania and schizophrenia.
Adult
10-15 mg PO qd; if needed, may increase dose gradually q2wk, not to exceed 30 mg/d
Pediatric
Not established
CYP450 3A4 and 2D6 isoenzyme substrate, thus, inhibitors (ie, ketoconazole, quinidine, fluoxetine, paroxetine) or inducers (ie, carbamazepine) may increase or decrease serum levels, respectively
Documented hypersensitivity
Pregnancy
C - Safety for use during pregnancy has not been established.
Precautions
Common adverse effects include headache, anxiety, somnolence, or insomnia; rare reports of tardive dyskinesia and neuroleptic malignant syndrome; may cause orthostatic hypotension, seizure, dysphagia, or suicidal ideation; hyperglycemia may occur and in some cases be extreme, resulting in ketoacidosis, hyperosmolar coma, or death
More on Mental Retardation |
| Overview: Mental Retardation |
| Differential Diagnoses & Workup: Mental Retardation |
 Treatment & Medication: Mental Retardation |
| Follow-up: Mental Retardation |
| References |
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Further Reading
Keywords
cognitive impairment, intelligence quotient, IQ less than 70, learning disability, Down syndrome, Fragile X syndrome, Prader-Willi syndrome, Angelman syndrome, Smith-Magenis syndrome, CATCH 22 (22q11 deletion) syndrome, DiGeorge syndrome, velocardiofacial syndrome, Williams syndrome, Wolf-Hirschhorn syndrome, Langer-Giedion syndrome, Miller-Dieker syndrome, tuberous sclerosis, Rubinstein-Taybi syndrome, Coffin-Lowry syndrome, Rett syndrome, Smith-Lemli-Opitz syndrome, fetal alcohol syndrome, fetal alcohol effects, cretinism, congenital hypothyroidism, congenital cytomegalovirus, congenital rubella, intraventricular hemorrhage, hypoxic-ischemic encephalopathy, traumatic brain injury, shaken baby syndrome, meningitis
