Comp., Prep., &c. Aloes is a complex resinous substance containing a body called aloin, which is its active or purgative principle. It is completely soluble in boiling water, and in alcohol or rectified spirit. The decoction deposits an impure resin or resinoid on cooling.
Phys. eff., Uses, &c. Aloes is a warm stimulating purgative, in doses of 3 to 10 gr.; whilst even 1 or 2 gr. seldom fail to produce one motion without pain or inconvenience. It is considered highly serviceable in hypochondriacal, hysterical, and dyspeptic affections, particularly in phlegmatic habits, and in cases arising from deficiency of bile. As an emmenagogue, and a vermifuge, few medicines are more valuable. It acts on the large intestines, and principally on the rectum; and, therefore, should be administered with caution, or only in small doses, where there is a tendency to prolapsus or piles, and in cases where uterine stimulants (as in pregnancy, &c.) would be improper. “It is remarkable with regard to it, that it operates almost to as good a purpose in a small as in a large dose; and one or two grains will produce one considerable dejection, and twenty grains will do no more, except it be that in the last dose (case) the operation will be attended with griping, &c. It is one of the best cures for habitual costiveness.” (Cullen.) Many of the effects complained of arise from its slow solubility in the primæ viæ, and may be obviated by administering it in a liquid form, or in a solid form combined with soap, which renders it freely soluble in the juices of the stomach.
Aloes is more frequently taken than, perhaps, any known purgative. It enters into the composition of a majority of the aperient medicines prescribed by the faculty, and forms the principal ingredient of nearly all the advertised purgative, antibilious, and universal pills of the nostrum-mongers. The fact of aloetic pills not acting until about 8 to 10 hours after being swallowed—so that if taken on retiring to rest at night they do not generally disturb the patient before the usual time of rising in the morning—has contributed more than anything else to make such remedies popular with parties whose habits or business avocations would be otherwise interfered with.
Aloes is also extensively used in veterinary
practice. It is the most valuable and reliable purgative for the horse of the whole materia medica; but is less to be depended on for cattle, sheep, and hogs. Barbadoes aloes is the best for this purpose. Cape aloes are, however, often employed, when 1-4th more must be given.—Dose (of the former), for a HORSE, 4 to 8 dr.;[32]—CATTLE, 3 to 6 dr. (followed by a purging drench);—HOGS, 5 to 15 gr.;—SHEEP, 15 to 30 gr.;[33]—DOGS (small ones), 10 to 30 gr., (middle-sized) 20 to 44, or even 60 gr., (large) 3⁄4 to 1 dr., or even 2 dr.
[32] Aloes takes from 18 to 30, or even 36 hours, to operate on a horse.
[33] Aloes, however large the dose, often fails to purge sheep. In very large quantities it is poisonous to them.
Aloes is also used in dyeing; and as a colouring matter in stains, lacquers, and varnishes. Aloes, and several of its preparations, are likewise extensively employed to adulterate porter.
Var. These, arranged in the order of their reputed medicinal value, are—Socotrine, Hepatic, Barbadoes, Cape, &c.; and alphabetically, as given below:—
Aloes, Barba′does. Syn. Aloes in Gourds; Al′oë Barbaden′sis, L., Ph. L. & E. Imported from Barbadoes and Jamaica, usually in gourds; sometimes in boxes. The best is the inspissated juice of the cut leaf of aloë vulga′′ris; an inferior quality is prepared from the decoction.—Char., &c. Opaque, lustreless, of a liver colour, a little tending to black, with a bitter nauseous taste, and a very disagreeable odour, especially when breathed on; powder a dull olive-yellow. It is the ‘hepatic’ aloes of most continental writers, and said to be the Αλοη of Dioscorides. It is more active than the other varieties of aloes; but is also more apt to occasion hæmorrhoids, and to gripe, than any of them.