The Smithsonian Magazine has a fascinating article on Prohibition and the rise of "medical beer" that was prescribed by doctors.

And in the early months of 1921, a dedicated group of brewers, physicians and imbibers attempted to convince the U.S. Congress that beer was nothing less than vital medicine. Whatever craven thirsts might have inspired its advocates, the right of physicians to prescribe "medical beer" was the subject of intense national debate, drawing the attention of officials at the highest levels of government and provoking arguments within the American Medical Association and other professional groups….

But if many doctors conceded the efficacy of hard liquor, the case of beer was rather more controversial. Beer’s champions often pointed to its relaxing qualities, and to its nutritional value. In a lengthy ode to British ale, for instance, one writer suggested that beer was so chock-full of vitamins that it had saved the "British race" from extinction during food-scarce plague years.

Other healers questioned such claims. Dr. Harvey Wiley, a prominent physician and an architect of the nation’s first food and drug laws, could barely contain his contempt for those who subscribed to such folk remedies. "There are no medical properties in beer, whatever may be said of it as a beverage," he pronounced in March 1921. "I never saw a prescription which contained beer as a remedial agent."…

On March 3, 1921, shortly before his last day as attorney general, Palmer issued an opinion declaring that the "beverage" clause of the 18th Amendment entitled doctors to prescribe beer at any time, under any circumstances and in any amount they saw fit. Wholesale druggists could take charge of selling beer. He also suggested that commercial drugstores could sell it from their soda fountains—though "never again beer over the saloon bar or in the hotel dining room."

Via Boing Boing.