system
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human
Rubbing alcohol or hydrogen peroxide?

I understand that this is not the place for medical advice but is there is a difference between the two or are they equally efficacious in terms of their aseptic properties? Or is one used over the other in certain circumstances?
gpt
Hydrogen peroxide is an inferior antiseptic(an anti-microbial used on skin or mucus membranes) because tissue catalases can break it down into O2 and H2O.  It can be used as a disinfectant (cleaning surfaces), however.


Alcohols are better because they are not broken down by enzymes as readily as hydrogen peroxide (your liver metabolizes alcohols but this is irrelevant when applying small amounts of alcohols to your skin or mucus membranes).  Ethanol is effective, but isopropanol is both less volatile and more potent so is preferred.  However, alcohols do not kill bacterial spores.  In fact, fatal infections have followed attempts to sterilize medical instruments with alcohols because of the danger of spores.


To sterilize most medical instruments hospitals will use something known as an autoclave.  It is essentially a giant pressure cooker, and uses steam at a pressure of around 15 lb/in^2 and a temperature of around 120 Celsius for roughly 15 minutes to kill all microbes and their spores.


To sterilize your skin for surgery surgeons will use iodine-based solutions like povidine-iodine(trade name: betadine), which are effective against even spores.  Furthermore, these solutions leave a lasting iodine residue meaning the effect continues post-application.



This isn't medical advice, simply a statement of fact regarding antimicrobials.