Medications that may interfere with catecholamines and metabolites include amphetamines and amphetamine-like compounds, appetite suppressants, bromocriptine, buspirone, caffeine, carbidopa-levodopa (Sinemet), clonidine, dexamethasone, diuretics (in doses sufficient to deplete sodium), ethanol, isoproterenol, labetalol, methyldopa (Aldomet), MAO inhibitors, nicotine, nose drops, propafenone (Rythmol), reserpine, theophylline, tricyclic antidepressants, and vasodilators. The effect of drugs on catecholamine results may not be predictable.
For optimum results, patient should be supine for 30 minutes prior to collection."Upright" ranges typically show epinephrine up to 900 pg/mL, and norepinephrine up to 700 pg/mL, and dopamine essentially unchanged.
Children, particularly those under 2 years of age, often show an elevated catecholamine response to stress.