The purpose of this study is to establish the influence of the non-steroidal candidate-drug pemirolast on allergen-induced airway obstruction and inflammation in allergic subjects with asthma. Pemirolast is an orally available inhibitor of the release of mast cell mediators. The study will therefore test the hypothesis that global inhibition of the mast cell, resulting in decreased production of most of its mediator molecules, will provide a highly significant anti-asthmatic effect.