The common aliphatic alcohols are good solvents, antiseptics, and disinfectants. They have germicidal activity that is logarithmically related to their lipid solubility. Potency increases with chain length.
Use of isopropyl alcohol for external antisepsis is increasing over ethyl alcohol due to the regulatory issues surrounding ethanol. It is also less expensive.
Alcohols have marked antibacterial action against vegetative cells but like many disinfectants do not destroy bacterial spores.
At UAF, we occasionally use 70% isopropyl alcohol as a preliminary cleaner, primarily for its use at a solvent. Its use is followed by a broader spectrum disinfectant (e.g. quaternary ammonium compounds, chlorhexidine, etc.). If the solvent activity of alcohol is not needed then use of a broader spectrum disinfectant is preferred over using alcohol as the sole disinfectant.
Use of 70% alcohol as the sole cleanser, particularly for a surgery area, is not adequate. We use iodine based soaps and/or solutions as the primary cleanser/disinfectant with 70% isopropyl alcohol as the final rinse in our surgical preps, prior to painting/spraying with full strength povidone-iodine solution.
Alcohols are irritating and can cause reddening and pruritis (itching) even on unbroken skin. If alcohol penetrates below the skin surface, it will destroy cellular protoplasm.