This is an ancient form of prescription; for although the term “Electarium” is first used by Cælius Aurelianus, yet the ἐκλὶκτον of Hippocrates, and the Antidotus, Confectio, Mithridatium, Diascordium, Opiatum, Orvietanum, Philonium, Theriaca, and Requies of other authors, were all Electuaries. They differ from Conserves in this, that the sugar in the latter preparations is in a greater proportion, and is intended to preserve the ingredients; whereas in the former, it is merely intended to impart convenience of form; see Confectiones. Electuaries are in general, extemporaneous preparations, composed of dry powders, formed into a proper consistence by the addition of syrup, honey, or mucilage; when however the latter substance is employed, the electuary very soon becomes dry and hard: and when common syrup is used, the compound is apt to candy, and in a day or two to grow too hard for use; this is owing to the crystallization of the sugar; Deyeux therefore states, that the syrup should be previously exposed to the heat of a stove so long as it forms any crystals, and that the residual liquor, which from the presence of some vegetable acid has no tendency to crystallize, may then be advantageously applied;—Melasses or Treacle may in some cases be employed, and from experiments which I have repeated with some care, I am enabled to state that the peculiar flavour of this liquid is entirely removed by a simple operation, which consists in diluting it with an equal weight of water, and then boiling it with about one eighth part of powdered charcoal for half an hour, when the liquor is to be strained, and reduced by gentle evaporation to a proper consistence;[[301]] and moreover it appears, that active vegetable powders retain their characteristic qualities when immersed in treacle, longer than in any other excipient.
In selecting and prescribing this form of exhibition, the following general rules should be observed.
I. Those substances which are nauseous, deliquescent, which require to be given in large doses, or which are incapable of forming an intimate union with syrup, as fixed oils, balsams, &c. should never be prescribed in the form of an electuary.
II. The quantity of syrup directed must be regulated by the nature and specific gravities of the substances which enter into their composition, viz.
1. Dry Vegetable Powders require twice their weight of syrup, or of honey.
2. Gummy and Resinous Powders require an equal weight.
3. Hard Mineral Substances should be formed into an electuary with some conserve, as they are too ponderous to remain suspended in syrup. It deserves also to be noticed, that in consequence of the readiness with which metallic preparations undergo change, it will be generally adviseable to keep the active ingredients in the form of powder, and to add them to the syrup only just before they are required; the Electuary of the French Pharmacopœia, which is commonly called “Opiata Mesenterica,” will furnish a good example, “quantumvis molle fuerit recens, progressu temporis, ob ferrum quod ipsi inest, mirè indurescit.”
LIQUID FORMS.
MISTURÆ. Mixtures.
These preparations are generally extemporaneous, in which different ingredients are mingled together in the liquid form, or, in which solid substances are diffused through liquid, by the medium of mucilage or syrup: for prescribing mixtures the following general rules may be laid down.