A series of N-[2-(dimethylamino)ethyl]-4-aryl-1-piperazinecarboxamides was synthesized and evaluated for antiallergy activity. Several derivatives had activity in the passive foot anaphylaxis (PFA) assay, an IgE-mediated model useful in the detection of compounds possessing antiallergic activity, but no derivative tested had activity at 10 mg/kg in the guinea pig anaphylaxis (GPA) assay. One analogue, N-[2-(dimethylamino)ethyl]-4-(4-fluorophenyl)-1-piperazinecarboxamide , had an IC50 = 310 nM for inhibition of tritiated mepyramine binding to H1 histaminic receptors isolated from guinea pig cerebral cortex.