Antiseptic, a substance used for preventing or arresting the spontaneous decomposition (fermentation or putrefaction) of animal and vegetable material. The kind of antiseptic which is required varies a good deal with the nature of the materials, each substance having - more or less - its own most fitting antiseptic.
The best known antiseptics are - (1) mineral acids, (2) common salt, (3) sugar, (4) spices, (5) ordinary alcohol, (6) some of the higher alcohols, especially phenol and thymol, (7) perchloride of mercury (corrosive sublimate). Perchloride of mercury has the reputation of being by far the most effective antiseptic; but is, unfortunately, a violent poison.
Antiseptic drugs are those which arrest putrefactive changes. Such changes are now known to be due to the growth of micro-organisms, which flourish luxuriantly in dead animal or vegetable matter. Antiseptics destroy the micro-organisms, and so prevent decomposition from taking place. Thus, anything which is inimical to the life of bacteria will have an antiseptic action. Some bacteria cannot live without a free supply of air; use is made of this fact in the preservation of tinned meats. Again, for the growth of micro-organisms an adequate supply of moisture is necessary, and this explains the readiness with which substances can be preserved when kept perfectly dry.
The modern treatment of wounds by antiseptic dressings presents one of the most important applications of these substances. The surface of a wound affords abundant scope for the development of bacteria, and in days gone by such development. was of far too common occurrence, wounds becoming foul and assuming a sloughing and gangrenous appearance. The surgeon of to-day, however, by the adoption of the most scrupulous cleanliness, and the use of antiseptic dressings, prevents the growth of bacteria in the wound, and thus ensures much more rapid healing and largely diminishes the danger to life.
Again, antiseptics are largely employed in disinfection. Many, if not all the infectious diseases, are due to bacteria, and hence the importance of destroying such germs by disinfecting rooms, bedding, clothing, and the like.
Antiseptics are sometimes given internally to fever-stricken patients, but here their use is a limited one, for, unfortunately, those substances which act most powerfully upon germs have, as a rule, a poisonous action upon the human body likewise.