Yeast or Barm, the scum or residuum which forms during the process of fermentation of Beer. It is a mass of minute cryptogamic plants (Torula cerevisi). It consists of two parts: - 1. Cell-walls, composed of a kind of Cellulose or Starch; and 2. The contents of the cells, composed of a proteine substance, and probably fat and oil.
Offlc. Prep. Cataplasma Fermenti (Beer Yeast fl. oz. vj.; Flour oz. xiv.; Water heated to 100° fl. oz. vj. Theyeast to be mixed with the water, and the flour to be stirred in. The mass to be placed near the fire till it rises).
Dose of Yeast, fl. drs. ij. - fl. oz. j.
In Typhus and Typhoid Fetters, Yeast has in some cases been given with signal benefit. Dr. Stoker,* after a trial of its powers for upwards of thirty years, speaks highly of its efficacy. He considers that it is well suited to every stage of Typhus, in which it can be retained by the stomach. It is generally easily taken, either alone or with any medicine that it may be advisable to join with it; and in the worst forms of the fever, when it is the most needed, it not only is seldom rejected by the stomach, but the patient often expresses a liking for it. Dr. Stoker found it act as a gentle laxative, but when this was not desirable, a few drops of T. Opii were added to each dose. He found petechiAe, black loaded tongue, &c, more effectually remedied by it than by any other medicine. In the most obstinate cases of tympanitic distension, he found enemas of Yeast and Assaftida the most efficacious remedies. It may be given in doses of two tablespoonfuls in water or Camphor mixture, every three hours; fl. oz. iv., with an equal quantity of gruel, may be administered as an enema. In quoting the above statement, Dr. Tweedie adds that he considers Yeast deserving of attention in the low forms of fever. More recently, it has been strongly advocated by Dr. Lamprey, who states that he cannot speak too highly of the stimulating and antiseptic properties of Yeast, given in the following formula: - CerevisiAe Fermenti fx., Camphor, 3ss , Ether. Nit. f3iv., M. Dose fj., every one, two, or three hours, according to the severity of the symptoms. It has also been used with signal benefit by Mr. Bennett§ of Gateshead.
Lamprey || states that he has found Yeast given internally, in combination with Camphor and Ether, have the effect of effectually correcting the ftor of the dejecta. It not only did this speedily, but diminished the frequency of the discharges. In the last stages it may prove also a valuable stimulant.
* On Continued Fever, Dub., 1829. Cyc. Pract. Med., vol. ii. p. 210. Dublin Quart. Journ., Aug. 1849.
§ Med. Gazette, Jan. 10, 1851. || Op. cit.
788. To Fetid, Sloughing, Gangrenous, and Cancerous Ulcers, the Yeast poultice (ut supra) is a valuable application. It tends to destroy the ftor, arrests the sloughing, assists in the separation of the dead parts, and establishes a healthy granulating surface. It occasionally produces great pain.
Mosse found that Yeast, in doses of a tablespoonful twice daily for adults, exercised a most beneficial influence. By this means he often effected a rapid and complete cure. As a remedy in Diabetes, it has been proposed, on chemical grounds, by Dr. W. B. Herapath, and he mentions a case in which he employed it (a tablespoonful twice or thrice daily) with satisfactory results. Its value requires confirmation. It has also been given in Scarlatina of malignant type.