Dextroamphetamineinteractions

Acidifying and Alkalinizing Agents: Agents that alter GI and urinary pH can alter blood levels of amphetamine. Acidifying agents can decrease amphetamine blood levels, while alkalinizing agents increase amphetamine blood levels

7.1 Drugs Having

Clinically Important Interactions with Amphetamine Table 3: Drugs Having Clinically Important Interactions with Amphetamines MAO Inhibitors (MAOI) Clinical Impact MAOI antidepressants slow amphetamine metabolism, increasing amphetamine’s effect on the release of norepinephrine and other monoamines from adrenergic nerve endings causing headaches and other signs of hypertensive crisis. Toxic neurological effects and malignant hyperpyrexia can occur, sometimes with fatal results. Intervention Do not administer XELSTRYM during or within 14 days following the administration of MAOI. Serotonergic Drugs Clinical Impact The concomitant use of XELSTRYM and serotonergic drugs increases the risk of serotonin syndrome. Intervention Initiate with lower doses and monitor patients for signs and symptoms of serotonin syndrome, particularly during XELSTRYM initiation or dosage increase. If serotonin syndrome occurs, discontinue XELSTRYM and the concomitant serotonergic drug(s). CYP2D6 Inhibitors Clinical Impact The concomitant use of XELSTRYM and CYP2D6 inhibitors may increase the exposure of XELSTRYM compared to the use of the drug alone, and increase the risk of serotonin syndrome. Intervention Initiate with lower doses and monitor patients for signs and symptoms of serotonin syndrome, particularly during XELSTRYM initiation and after a dosage increase. If serotonin syndrome occurs, discontinue XELSTRYM and the CYP2D6 inhibitor. Alkalinizing Agents Clinical Impact Urinary alkalinizing agents can increase blood levels and potentiate the action of amphetamine. Intervention Co-administration of XELSTRYM and urinary alkalinizing agents should be avoided. Acidifying Agents Clinical Impact Urinary acidifying agents can lower blood levels and efficacy of amphetamines. Intervention Increase dose based on clinical response. Tricyclic Antidepressants Clinical Impact May enhance the activity of tricyclic or sympathomimetic agents causing striking and sustained increases in the concentration of dextroamphetamine in the brain; cardiovascular effects can be potentiated. Intervention Monitor frequently and adjust or use alternative therapy based on clinical response.

7.2 Drugs Having

No Clinically Important Interactions with Amphetamine From a pharmacokinetic perspective, no dose adjustment of XELSTRYM is necessary when XELSTRYM is co-administered with guanfacine, venlafaxine, or omeprazole. In addition, no dose adjustment of guanfacine or venlafaxine is needed when XELSTRYM is co-administered. From a pharmacokinetic perspective, no dose adjustment for drugs that are substrates of CYP1A2 (e.g. theophylline, duloxetine, melatonin), CYP2D6 (e.g. atomoxetine, desipramine, venlafaxine), CYP2C19 (e.g. omeprazole, lansoprazole, clobazam), and CYP3A4 (e.g. midazolam, pimozide, simvastatin) is necessary when XELSTRYM is co-administered.