The combination of ipratropium and albuterol is more effective than either agent alone.

Anticholinergic bronchodilators have been used since the beginning of recorded time. The datura genus of plants that contains anticholinergic alkaloids, including atropine, has been used by man for several thousand years for "recreational and various nefarious purposes."1 The anticholinergics have been used as bronchodilators for at least 300 years.2 Stramonium powders, burned and inhaled, are still used worldwide, often in underdeveloped countries.3'4 Several anticholinergics are regularly prescribed by physicians worldwide, including atropine, ipratropium bromide, thiazinamium, oxitropium, and glycopyrrolate. Only ipratropium bromide is licensed for use in the United States. The origins of sympathomimetic agonist bronchodilators can be traced to the Chinese herb, ma-huang, and the derivative, ephedrine, which has both aand :-agonist properties. Inhaled d-agonists were introduced into modern medicine in the mid1940s.5 Isoproterenol hydrochloride (Isuprel) was found to have a more selective f-agonist than epinephrine.6 Isoproterenol rapidly replaced epinephrine as a potent, but only short-acting, inhaled bron-