The best position for their application is between the shoulders, and they should be kept open for some weeks. They are, however, rarely employed at the present day, being much more unmanageable and less efficacious than counter-irritation by Tartar Emetic ointment, or by a seton or issue.
They are chiefly applicable in the second stage, after the employment of depletion and an emetic; and they should be applied between the shoulders, at the nape of the neck, or on the epigastrium, but never to the throat; in this last situation they are most objectionable, and will probably increase the severity of the symptoms.
2973. In Cystitis and Inflammation of the Kidneys, blisters were formerly considered to be contra-indicated, from the fear that the Cantharides would increase the irritation of the parts, and aggravate the symptoms. This they probably would do, if applied without proper precautions (ante); but if these be attended to, they may be used, not only with safety, but with advantage.
* Op. cit.
Lib. of Med., vol. iii.
Obs. on Diseases of the Larynx and Trachea.
Tilt* advises, after the application of leeches, the use of blisters (four or five inches long by three in breadth) over the ovarian regions. He directs the blister to be carefully camphorated, so as to guard against dysuria. The epidermis must not be removed from the skin, and the irritated surface should be healed as soon as possible.
Churchill states that he has often derived great benefit from a blister applied to the sacrum, and either kept open or repeated. The value of blisters to the Cervix Uteri in the minor idiopathic Affections of the Uterus and Ovaria is shown by numerous cases cited by Dr. Johns. The best and most speedy way of effecting this is by means of a strong solution of Cantharides applied by a camel's-hair pencil An anodyne should be added to prevent pain. No unpleasant symptoms generally follow; cicatrization soon takes place. A speculum is necessary to bring the parts into full view. Care should be taken that the fluid does not extend beyond the parts.
2976. In Hypertrophy of the Uterus, blisters applied to the sacrum or inguinal regions often afford great relief, and promote reduction. (Dr. Oldham.§)
2977. In Incontinence of Urine in Children, when other remedies fail, a blister over the sacrum, repeated according to circumstances, often proves effectual.
Milton,|| who considers that every gonorrhoea or gleet, however obstinate, may, if uncomplicated, be cured by blistering singly, or combined with the use of injection (Zinci Sulph. 3j., Aq. Oj.). Before applying the blister, the hair at the root of the penis is to be cut off, a piece of paper is then to be fitted on the penis, and cut till it exactly covers it, from the root to within half an inch of the mouth of the urethra. This is then laid down on the blister, which is cut out by it, wrapped round the penis and fastened with threads. Care is necessary to prevent the ointment spreading to the scrotum. In mild cases, it may remain on an hour and a half, and the vesicated spots dressed with Zinc ointment; a T bandage should be worn.
* Obs. on Ovaritis, Lancet, March and April 1849. v Midwifery, 3rd Ed., p. 61.
Dub. Quart. Journ. of Med. Sci., May 1857. § Guy's Hosp. Reports, Oct. 1848. || Med. Times, Sept. 20, 1851.
In Acute Peritonitis and Enteritis, blistering the abdomen, in the early stage, is inadvisable, as it interferes with the application of leeches, poultices, fomentations, and other local measures, from which unequivocal benefit is derived. Occasionally, however, in the advanced stages, particularly if effusion has taken place, blisters may be used with advantage.
2980. In obstinate Subacute Diarrhoea, a blister to the abdomen is sometimes effectual, when all other measures have failed. It may be used in conjunction with other remedies.
2981. In the Collapse of Cholera, flying blisters (ante) may be applied to the epigastrium, the region of the heart, &c. Occasionally they prove highly serviceable in reviving the patient, and restoring the vital energies, but they more frequently are of little avail. In some of the sequences of cholera, their efficacy is undoubted.