ABSTRACT
I. COMMERCIALLY AVAILABLE ALLERGEN VACCINES Allergen immunotherapy is appropriately performed with vaccines of inhalant allergens or the venom from stinging insects. These vaccines are prepared in the United States from standardized or unstandardized extracts in a variety of formulations: (1) lyophilized, adsorbed to aluminum or in solution; or (2) phosphate-buffered saline containing human serum albumin or glycerin with or without phenol. Potency is expressed in terms of bioequivalent allergen units (BAU), content of the major allergen, weight by volume (wt/vol), or protein nitrogen units (PNU) per mI.
