An advertisement for a recent edition of the "Red Book," which lists all of the 140,000 medicaments handled by pharmacists and available to physicians for patients, states that "14,000 new drugs" were issued by drug manufacturers in 1953. In actuality, there were few really new drugs. The number given represents some truly introduced for the first time, such as new salts, new derivatives, and, in many cases, new mixtures (as an antibiotic with an antihistaminic). Some of these drugs represent a new form or type of administration or merely a new packaging of an old drug. These old drugs are, however, not too old, in that 90% of those most commonly prescribed have been discovered within the last 25 years. These truly new-old drugs, such as the sulfonamides, the antibiotics, the antihistaminics (and their isomers), and the steroid hormones, are distinguished by their potency. Many, although not all, possess multiple