This section is from the book "A Text-Book Of Materia Medica And Pharmacy For Medical Students", by Velyien Ewart Henderson. Also available from Amazon: A Text-Book of Materia Medica and Pharmacy for Medical Students.
By means of an enema antiseptics may be applied to the surface of the rectum and a part of the colon. If the antiseptic is readily absorbed or powerful in its action on mucous membranes, e.g. Acidum Carbolicum, only a small quantity of it may be prescribed in a large bulk of water. If relatively insoluble, e.g. Argyrol, or Boracic Acid, a much stronger solution may be used. Enemata containing bitters and astringents, - Quassia, Tannic Acid, Kino, are sometimes applied to drive out pin-worms and to act as mild astringents.
An enema is frequently employed to soften hardened faeces or to bring about defęcation. For these purposes either some bland fluid, e.g. Olive Oil, Normal Saline, or Mucilage of Starch is used in large quantities (2-3 pints) as these mechanically dilate the bowel and set up reflex movements. In order to produce defęcation alone a much smaller quantity of fluid may be used if it contains some drug which acts as a local irritant to the sensory nerve endings, e.g. Turpentine, Mustard, Aloes.
Nourishment is often given to those whose stomach is deranged, by means of an enema. In this case a bulk of more than three or four ounces can rarely be given. The food must be fluid, nonirritant, and highly nu-tritous. Eggs, milk, oil, alcohol, or mixtures of these with water, are common ingredients of this type of enema. In order to aid in their retention the fluid should be warmed to the temperature of the body, should be given slowly, and the patient kept in a prone position.
Some of the pharmacopaeial suppositories are intended to produce local antiseptic or astringent actions in the bowel, e.g. those of Phenol. Iodoform, Tannic Acid, and Lead; that of Glycerin to aid in defęcation.
For application to the Vagina. Drugs are only given by the Vagina for their local effect. Suppositories for this purpose are usually known as Pessaries, - fluid washes as Douches. The most frequently employed vaginal antiseptics are Mercuric Perchloride 1-2000-5000, Silver Nitrate 2-1000-500, Argyrol, and Cresylic Acid, Potassium Permanganate 1-1000-5000. Vaginal Tampons impregnated with active drugs in glycerin are sometimes employed.
For application to the Urethra and Bladder. Here also a purely local effect is the only one ever sought. Astringents and antiseptics are administered to the urethra and bladder in the form of douches whose solvent is some bland fluid, usually water or Oil. Suppositories for the urethra are known as Bougies. The antiseptics mentioned above for the vagina are very commonly employed here also.
As the bulk of fluid necessary for a douche is very often a large one it is a common expedient of prescribers to order for their patient either powders or concentrated solutions to which large quantities of water such as can be readily measured in the household, pints or quarts, are to be added as needed.
For application to the Conjunctiva. This is the most delicate of all the mucous surfaces and in consequence as Collyria only weak solutions of astringents and antiseptics may be employed and usually the weaker members of these series are chosen, - Sulphate of Zinc 1-250, Silver Nitrate 1-200-500, Argyrol and other colloidal preparations of Silver may be used in stronger solutions up to 5%, Boracic Acid and Borax in 2% solutions. Solutions of these salts are frequently made with Camphor Water as a vehicle.
In order to produce their local effects after absorption, the Mydriatics and Miotics may be prescribed, as the Lamellae or more usually in solution, Atropine in 1%, Cocaine in 5%, Physostigmine in 1/2%. Homatropine in 2%, Pilocarpine in 1/2 - 1%, Ethylmorphine in 1%.
All solutions especially if they contain inorganic salts should be carefully filtered so as to make certain that they are free from gritty particles of dirt, which would irritate the sensitive mucous surface.
Drugs may also be applied to the Conjunctiva in solution in oil or in the form of an ointment; such bases must be bland, free from fatty acids and from insoluble particles. Liquid and yellow (not white) Soft Paraffin, conform best to these requirements.
For application to the mouth and Respiratory Passages. Antiseptic and astringent solutions are frequently given in the form of douches, gargles (Gargarismata), mouth washes (Collutoria). The chief antiseptics used are Boracic Acid, Borax, Potassium Chlorate, all in about 4% solution, - Eucalyptol and Thymol. Of the astringents the Liquor or Tincture of Ferric Chloride 2-3%, Tannic Acid 1-2%, Tincture of Kino 2% Alum 1%, Potassium Permanganate 1-1000, are frequently used preparations. Antiseptics or astringents are often applied by means of a swab and in this case stronger solutions may be used, e.g. Silver Nitrate 1/2 - 1 - 2%.
The Larynx and upper parts of the Nose can also be reached by means of douches. For the nose the solution should be a bland one if a thorough application is to be hoped for. A saline solution of the concentration of normal saline which contains as well mild antiseptics such as Thymol and Eucalyptol or a solution of one of the colloidal silver preparations are very popular. Such solutions may be very well applied by means of an atomizer. Solutions for use in an atomizer are very frequently made with Liquid Paraffin as a solvent.
The trachea, bronchioles, and alveoli, can only be reached by a very fine spray or by volatile substances which can be inhaled. Most of the antiseptics which on account of their volatility could be applied in this way, are either too irritant or so readily absorbed that they would produce unwished-for remote actions. And though good may be done in some cases by applying the weaker antiseptics it is rarely that they can be brought to the diseased area in sufficient concentration or for sufficient duration of time, to produce any marked effect. The antiseptics that may be used in this way include Benzoin, Thymol, Eucalyptol, Creosote. The Compound Tincture of Benzoin is a favorite preparation. Volatization is usually brought about by pouring a strong alcoholic solution of the antiseptic upon the surface of boiling water and inhaling the fumes which arise. In this way, not only the antiseptic, but also water vapour which serves to allay the feeling of dryness of the inflamed mucous membrane, is inhaled. Volatile substances such as Ether, Chloroform, and Amyl nitrite readily produce a remote action when inhaled.