l66 PHARMACEUTICAL BACTERIOLOGY. 



A. Carbolic Acid {Phenol). — ^Very widely used, in strengths of from i to S 

 per cent. As a disinfecting wash for all manner of septic things, a s per cent, 

 solution is commonly employed. A 2.5 per cent, (also the 5 per cent.) 

 solution is much used as a disinfectant for hands and the skin generally 

 and for septic wound irrigation. A 0.5 to i per cent, solution is used as a 

 mouth wash and gargle. Phenol does not kill spores hence should not be used 

 after anthrax, tetanus, malignant edema and other diseases due to spore 

 bearing bacteria. Phenol coagulates albumen, but not as actively as does 

 corrosive sublimate. 



Carbolic acid (5 per cent.) is much used for disinfecting liquid discharges 

 in dysentery, typhoid, cholera, and for the disinfection of sputa and expecto- 

 ra,tions in tuberculosis, in pneumonia, etc., using about two times as much 

 of the disinfectant as material to be disinfected, allowing the mixture to 

 stand for several hours at least. 



A 5 per cent, solution may be prepared as follows: 



Carbolic acid (95 per cent.), 6 1/2 oz. 



. Water, i gal. 



Shake thoroughly uhtU all of the acid is dissolved. 



Carbolic acid does not destroy, bleach or discolor cloth fabric, does not 

 corrode metal, has a marked characteristic odor, is a powerful escharotic 

 poison, and the crystals are readily liquefied by heat, by alcohol and by water. 



B. Liquor Cresolis Compositus U. S. P. — This most efficient germicide 

 is a liquid soap with 50 per cent, cresol, miscible in all proportions with 

 water. The cresols used should have a high boiling-point (187° to 189° C). 

 The germicidal powers of this substance is nearly double that of carbolic 

 acid. It does not coagulate albuminous matter and kills spores. 



There are a number of germicides similar to carbolic acid having marked 

 germicidal properties including creolin, cresol and lysol. These are some- 

 what superior to carbolic acid. Lysol is a cresol mixed with soap which 

 greatly facilitates the solution of the cresol, being therefore similar to liq. 

 cres. comp. U. S. P. They all kill spores. 



C. Tricresol. — Tricresol is a mixture of orthocresol, metacresol and para- 

 cresol. It dissolves in water in the proportion of 2.5 per cent, and is about 

 three times as active as carbolic acid. It is less irritating than carbolic 

 acid for which reason it is preferred in sterilizing sera (about 0.25 per cent.) 

 and other solutions intended for hypodermic use. Tricresol kills spores and 

 albuminous matter does not interfere with its action. 



Tricresol, cresol, lysol, solved, solutol and creolin are usually employed 

 (as germicides) in i per cent, solutions and are generally conceded to be 

 equal to about 2.5 per cent, solutions of phenol. They, however, have no 

 superiority over the liq. cres. comp. U. S. P. 



D. Formalin. — The 40 per cent, commercial article is used. It has 



