Alcohol as a solvent
When considering alcohol, or more precisely ethyl alcohol or ethanol, most people recognize its place in society as a common recreational drug. Few any longer associate its use with medicine, but the development of higher quality and concentrated alcohol has paralleled advances in pharmacy through the ages. It is second only to water in importance as a solvent in medicine and is used particularly to extract active constituents from inert parts of crude drugs. This concentrates the medicinally active compounds and makes the remedy easier to dispense and consume while also improving its absorption. The compounds that normally dissolve in alcohol include alkaloids, glycosides, resins, and volatile oils but not polysaccharides, gums, sugars, or proteins. Combined with water to make a hydroalcoholic solvent, it acts as a preservative by preventing hydrolysis and inhibiting fermentation that would occur if water was used alone.
Early discoveries and uses
Probably all early civilizations produced fermented beverages from local produce. In the areas of China, Mesopotamia, and Egypt it is known that these beverages were sometimes used to administer herbal medicines. In Greece the practice of mixing herbs in wine began before the time of Hippocrates who was born in 460 B.C.. This practice spread throughout Europe and continued through the Middle Ages. The process of distillation was probably discovered about 900 B.C. in China, but alchemists at Islamic universities are credited with its application to medicine over 1500 years later. In the Middle East the Persians Geber (8th cent.) and Rhazes (10th cent.) developed the art of distillation and used it to concentrate alcohol which was then taken as an anaesthetic. In the late 10th century in Spain the Arab surgeon Abulcasis described using distilled alcohol as a solvent for drugs.
From the 12th to the 14th centuries alchemists in Europe began experimenting with the distillation of many items, but medicines were still mostly given as infusions or decoctions of single herbs. Arabic writings and universities in Spain began to influence Christian schools of medicine in Italy and France. Two contemporary 13th century Spanish alchemists, Arnold of Villanova and Raymond Lully, introduced wine spirits, which they called aqua vitae (water of life), as a solvent into European medicine. This later became known as brandy, shortened from the Dutch term for "burnt wine." In the 14th century during the Black Death brandy began to be used as a medicine by itself. It was thought of as a polycrest, a remedy of many virtues. By the next century brandy had also become popular as a recreational beverage. Yet wines and vinegars were still preferred for the extraction of herbs. In Ireland, England, Scotland, and northern Europe alcohol was being distilled from fermented grain beverages. It was given the name whiskey, a shortened form of the Gaelic term for "water of life." The pot stills used to distill wine and beer at that time could concentrate the alcohol to as much as 65-70%.
In the 16th century the Swiss physician Paracelsus popularized the use of distilled alcohol as a solvent to prepare tinctures from herbs and chemicals. The production of compound alcoholic extracts called elixirs then began to flourish in European monasteries. These elixirs contained from dozens to over 100 different herbs and were prepared in stages with secrete, complex procedures. At that time most were bitter and were usually taken before meals as digestive tonics. Some of these elixirs were also sweetened and are now sold as liqueurs such as Benedictine and Chartreuse.