ympathomimetic agents; d -amphetamine with desipramine or protriptyline and possibly other tricyclics cause striking and sustained increases in the concentration of d -amphetamine in the brain; cardiovascular effects can be potentiated. cyp2d6 inhibitors the concomitant use of dextroamphetamine sulfate tablets and cyp2d6 inhibitors may increase the exposure of dextroamphetamine sulfate tablets compared to the use of the drug alone and increase the risk of serotonin syndrome. initiate with lower doses and monitor patients for signs and symptoms of serotonin syndrome particularly during dextroamphetamine sulfate tablets initiation and after a dosage increase. if serotonin syndrome occurs, discontinue dextroamphetamine sulfate tablets and the cyp2d6 inhibitor [see warnings , overdosage ]. examples of cyp2d6 inhibitors include paroxetine and fluoxetine (also serotonergic drugs), quinidine, ritonavir. serotonergic drugs the concomitant use of dextroamphetamine sulfate tablets and serotonergic drugs increases the risk of serotonin syndrome. initiate with lower doses and monitor patients for signs and symptoms of serotonin syndrome, particularly during dextroamphetamine sulfate tablets initiation or dosage increase. if serotonin syndrome occurs, discontinue dextroamphetamine sulfate tablets and the concomitant serotonergic drug(s) [see warnings and precautions ]. examples of serotonergic drugs include selective serotonin reuptake inhibitors (ssri), serotonin norepinephrine reuptake inhibitors (snri), triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, tryptophan, buspirone, st. john's wort. mao inhibitors maoi antidepressants, as well as a metabolite of furazolidone, slow amphetamine metabolism. this slowing potentiates amphetamines, increasing their effect on the release of norepinephrine and other monoamines from adrenergic nerve endings; this can cause headaches and other signs of hypertensive crisis. a variety of neurological toxic effects and malignant hyperpyrexia can occur, sometimes with fatal results. antihistamines amphetamines may counteract the sedative effect of antihistamines. antihypertensives amphetamines may antagonize the hypotensive effects of antihypertensives. chlorpromazine chlorpromazine blocks dopamine and norepinephrine reuptake, thus inhibiting the central stimulant effects of amphetamines, and can be used to treat amphetamine poisoning. ethosuximide amphetamines may delay intestinal absorption of ethosuximide. haloperidol haloperidol blocks dopamine and norepinephrine reuptake, thus inhibiting the central stimulant effects of amphetamines. lithium carbonate the stimulatory effects of amphetamines may be inhibited by lithium carbonate. meperidine amphetamines potentiate the analgesic effect of meperidine. methenamine therapy urinary excretion of amphetamines is increased, and efficacy is reduced, by acidifying agents used in methenamine therapy. norepinephrine amphetamines enhance the adrenergic effect of norepinephrine. phenobarbital amphetamines may delay intestinal absorption of phenobarbital; co-administration of phenobarbital may produce a synergistic anticonvulsant action. phenytoin amphetamines may delay intestinal absorption of phenytoin; co-administration of phenytoin may produce a synergistic anticonvulsant action. propoxyphene in cases of propoxyphene overdosage, amphetamine cns stimulation is potentiated and fatal convulsions can occur. veratrum alkaloids amphetamines inhibit the hypotensive effect of veratrum alkaloids.

hildren of having serious structural cardiac abnormalities, cardiomyopathy, serious heart rhythm abnormalities, coronary artery disease, or other serious cardiac problems. adults with such abnormalities should also generally not be treated with stimulant drugs (see contraindications ). hypertension and other cardiovascular conditions stimulant medications cause a modest increase in average blood pressure (about 2-4 mmhg) and average heart rate (about 3-6 bpm), and individuals may have larger increases. while the mean changes alone would not be expected to have short-term consequences, all patients should be monitored for larger changes in heart rate and blood pressure. caution is indicated in treating patients whose underlying medical conditions might be compromised by increases in blood pressure or heart rate, e.g., those with pre-existing hypertension, heart failure, recent myocardial infarction, or ventricular arrhythmia (see contraindications ). assessing cardiovascular status in patients being treated with stimulant medications children, adolescents, or adults who are being considered for treatment with stimulant medications should have a careful history (including assessment for a family history of sudden death or ventricular arrhythmia) and physical exam to assess for the presence of cardiac disease, and should receive further cardiac evaluation if findings suggest such disease (e.g., electrocardiogram and echocardiogram). patients who develop symptoms such as exertional chest pain, unexplained syncope, or other symptoms suggestive of cardiac disease during stimulant treatment should undergo a prompt cardiac evaluation. psychiatric adverse events pre-existing psychosis administration of stimulants may exacerbate symptoms of behavior disturbance and thought disorder in patients with a pre-existing psychotic disorder. bipolar illness particular care should be taken in using stimulants to treat adhd in patients with comorbid bipolar disorder because of concern for possible induction of a mixed/manic episode in such patients. prior to initiating treatment with a stimulant, patients with comorbid depressive symptoms should be adequately screened to determine if they are at risk for bipolar disorder; such screening should include a detailed psychiatric history, including a family history of suicide, bipolar disorder, and depression. emergence of new psychotic or manic symptoms treatment emergent psychotic or manic symptoms, e.g., hallucinations, delusional thinking, or mania in children and adolescents without a prior history of psychotic illness or mania can be caused by stimulants at usual doses. if such symptoms occur, consideration should be given to a possible causal role of the stimulant, and discontinuation of treatment may be appropriate. in a pooled analysis of multiple short-term, placebo-controlled studies, such symptoms occurred in about 0.1% (4 patients with events out of 3,482 exposed to methylphenidate or amphetamine for several weeks at usual doses) of stimulant-treated patients compared to 0 in placebo-treated patients. aggression aggressive behavior or hostility is often observed in children and adolescents with adhd, and has been reported in clinical trials and the postmarketing experience of some medications indicated for the treatment of adhd. although there is no systematic evidence that stimulants cause aggressive behavior or hostility, patients beginning treatment for adhd should be monitored for the appearance of, or worsening of, aggressive behavior or hostility. long-term suppression of growth careful follow-up of weight and height in children ages 7 to 10 years who were randomized to either methylphenidate or non-medication treatment groups over 14 months, as well as in naturalistic subgroups of newly methylphenidate-treated and non-medication treated children over 36 months (to the ages of 10 to 13 years), suggests that consistently medicated children (i.e., treatment for 7 days per week throughout the year) have a temporary slowing in growth rate (on average, a total of about 2 cm less growth in height and 2.7 kg less growth in weight over 3 years), without evidence of growth rebound during this period of development. published data are inadequate to determine whether chronic use of amphetamines may cause a similar suppression of growth, however, it is anticipated that they likely have this effect as well. therefore, growth should be monitored during treatment with stimulants, and patients who are not growing or gaining height or weight as expected may need to have their treatment interrupted. seizures there is some clinical evidence that stimulants may lower the convulsive threshold in patients with prior history of seizures, in patients with prior eeg abnormalities in absence of seizures, and, very rarely, in patients without a history of seizures and no prior eeg evidence of seizures. in the presence of seizures, the drug should be discontinued. peripheral vasculopathy, including raynaud's phenomenon stimulants, including dextroamphetamine sulfate tablets, used to treat adhd are associated with peripheral vasculopathy, including raynaud's phenomenon. signs and symptoms are usually intermittent and mild; however, very rare sequelae include digital ulcerations and/or soft tissue breakdown. effects of peripheral vasculopathy, including raynaud's phenomenon, were observed in post-marketing reports at different times and at therapeutic doses in all age groups throughout the course of treatment. signs and symptoms generally improve after reduction in dose or discontinuation of drug. careful observation for digital changes is necessary during treatment with adhd stimulants. further clinical evaluation (e.g., rheumatology referral) may be appropriate for certain patients. serotonin syndrome serotonin syndrome, a potentially life-threatening reaction, may occur when amphetamines are used in combination with other drugs that affect the serotonergic neurotransmitter systems such as monoamine oxidase inhibitors (maois), selective serotonin reuptake inhibitors (ssris), serotonin norepinephrine reuptake inhibitors (snris), triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, tryptophan, buspirone, and st. john's wort [see drug interactions]. amphetamines and amphetamine derivatives are known to be metabolized, to some degree, by cytochrome p450 2d6 (cyp2d6) and display minor inhibition of cyp2d6 metabolism [see clinical pharmacology ]. the potential for a pharmacokinetic interaction exists with the co- administration of cyp2d6 inhibitors which may increase the risk with increased exposure to dextroamphetamine sulfate tablets. in these situations, consider an alternative non-serotonergic drug or an alternative drug that does not inhibit cyp2d6 [see drug interactions ]. serotonin syndrome symptoms may include mental status changes (e.g., agitation, hallucinations, delirium, and coma), autonomic instability (e.g., tachycardia, labile blood pressure, dizziness, diaphoresis, flushing, hyperthermia), neuromuscular symptoms (e.g., tremor, rigidity, myoclonus, hyperreflexia, incoordination), seizures, and/or gastrointestinal symptoms (e.g., nausea, vomiting, diarrhea). concomitant use of dextroamphetamine sulfate tablets with maoi drugs is contraindicated [see contraindications ]. discontinue treatment with dextroamphetamine sulfate tablets and any concomitant serotonergic agents immediately if the above symptoms occur, and initiate supportive symptomatic treatment. if concomitant use of dextroamphetamine sulfate tablets with other serotonergic drugs or cyp2d6 inhibitors is clinically warranted, initiate dextroamphetamine sulfate tablets with lower doses, monitor patients for the emergence of serotonin syndrome during drug initiation or titration, and inform patients of the increased risk for serotonin syndrome. visual disturbance difficulties with accommodation and blurring of vision have been reported with stimulant treatment.

activity not recommended for pediatric patients under 3 years of age. in pediatric patients from 3 to 5 years of age, start with 2.5 mg daily; daily dosage may be raised in increments of 2.5 mg at weekly intervals until optimal response is obtained. in pediatric patients 6 years of age and older, start with 5 mg once or twice daily; daily dosage may be raised in increments of 5 mg at weekly intervals until optimal response is obtained. only in rare cases will it be necessary to exceed a total of 40 mg per day. give first dose on awakening; additional doses (1 or 2) at intervals of 4 to 6 hours. where possible, drug administration should be interrupted occasionally to determine if there is a recurrence of behavioral symptoms sufficient to require continued therapy.

ympathomimetic agents; d -amphetamine with desipramine or protriptyline and possibly other tricyclics cause striking and sustained increases in the concentration of d -amphetamine in the brain; cardiovascular effects can be potentiated. cyp2d6 inhibitors the concomitant use of dextroamphetamine sulfate tablets and cyp2d6 inhibitors may increase the exposure of dextroamphetamine sulfate tablets compared to the use of the drug alone and increase the risk of serotonin syndrome. initiate with lower doses and monitor patients for signs and symptoms of serotonin syndrome particularly during dextroamphetamine sulfate tablets initiation and after a dosage increase. if serotonin syndrome occurs, discontinue dextroamphetamine sulfate tablets and the cyp2d6 inhibitor [see warnings , overdosage ]. examples of cyp2d6 inhibitors include paroxetine and fluoxetine (also serotonergic drugs), quinidine, ritonavir. serotonergic drugs the concomitant use of dextroamphetamine sulfate tablets and serotonergic drugs increases the risk of serotonin syndrome. initiate with lower doses and monitor patients for signs and symptoms of serotonin syndrome, particularly during dextroamphetamine sulfate tablets initiation or dosage increase. if serotonin syndrome occurs, discontinue dextroamphetamine sulfate tablets and the concomitant serotonergic drug(s) [see warnings and precautions ]. examples of serotonergic drugs include selective serotonin reuptake inhibitors (ssri), serotonin norepinephrine reuptake inhibitors (snri), triptans, tricyclic antidepressants, fentanyl, lithium, tramadol, tryptophan, buspirone, st. john's wort. mao inhibitors maoi antidepressants, as well as a metabolite of furazolidone, slow amphetamine metabolism. this slowing potentiates amphetamines, increasing their effect on the release of norepinephrine and other monoamines from adrenergic nerve endings; this can cause headaches and other signs of hypertensive crisis. a variety of neurological toxic effects and malignant hyperpyrexia can occur, sometimes with fatal results. antihistamines amphetamines may counteract the sedative effect of antihistamines. antihypertensives amphetamines may antagonize the hypotensive effects of antihypertensives. chlorpromazine chlorpromazine blocks dopamine and norepinephrine reuptake, thus inhibiting the central stimulant effects of amphetamines, and can be used to treat amphetamine poisoning. ethosuximide amphetamines may delay intestinal absorption of ethosuximide. haloperidol haloperidol blocks dopamine and norepinephrine reuptake, thus inhibiting the central stimulant effects of amphetamines. lithium carbonate the stimulatory effects of amphetamines may be inhibited by lithium carbonate. meperidine amphetamines potentiate the analgesic effect of meperidine. methenamine therapy urinary excretion of amphetamines is increased, and efficacy is reduced, by acidifying agents used in methenamine therapy. norepinephrine amphetamines enhance the adrenergic effect of norepinephrine. phenobarbital amphetamines may delay intestinal absorption of phenobarbital; co-administration of phenobarbital may produce a synergistic anticonvulsant action. phenytoin amphetamines may delay intestinal absorption of phenytoin; co-administration of phenytoin may produce a synergistic anticonvulsant action. propoxyphene in cases of propoxyphene overdosage, amphetamine cns stimulation is potentiated and fatal convulsions can occur. veratrum alkaloids amphetamines inhibit the hypotensive effect of veratrum alkaloids.

experience symptoms of withdrawal as demonstrated by dysphoria, including agitation, and significant lassitude.

the complete history and evaluation of the pediatric patient. the decision to prescribe amphetamines should depend on the physician's assessment of the chronicity and severity of the pediatric patient's symptoms and their appropriateness for his/her age. prescription should not depend solely on the presence of one or more of the behavioral characteristics. when these symptoms are associated with acute stress reactions, treatment with amphetamines is usually not indicated.

sma concentrations were obtained approximately 8 hours after dosing. the average c max was 23.5 ng/ml. the average plasma t 1/2 was similar for both the tablet and sustained-release capsule and was approximately 12 hours. in 12 healthy subjects, the rate and extent of dextroamphetamine absorption were similar following administration of the sustained-release capsule formulation in the fed (58 to 75 gm fat) and fasted state.

ynaud's phenomenon] instruct patients beginning treatment with dextroamphetamine sulfate tablets about the risk of peripheral vasculopathy, including raynaud's phenomenon, and associated signs and symptoms: fingers or toes may feel numb, cool, painful, and/or may change color from pale, to blue, to red. instruct patients to report to their physician any new numbness, pain, skin color change, or sensitivity to temperature in fingers or toes. instruct patients to call their physician immediately with any signs of unexplained wounds appearing on fingers or toes while taking dextroamphetamine sulfate tablets. further clinical evaluation (e.g., rheumatology referral) may be appropriate for certain patients.