Isopropyl vs ethanol for disinfection

Herkimer P Shagnasty

Herkimer P Shagnasty

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I always cleaned the cartridge on my injector pen before I attach a new needle tip, with a disposable isopropyl pad. I had to fold over a corner, mash it in there and twist. I was never sure how well I was actually cleaning it.

I bought some alcohol swabsticks on Amazon thinking they would work better. They do! So much easier to reach the recessed rubber stopper on the cartridge. You bend the stick to release the alcohol, presto.

I was surprised to find out they were filled with ethanol instead of isopropyl. According to Dr. Google it works just as well. Anybody have any thoughts on this?

I've been around a lot of clinical settings and never noticed ethanol being used.
 
This looks like a good idea. I just bought some. I was also folding wipes to fit into the small space on my pens. As long as the isopropyl alcohol doesn't degrade the stopper, this should be fine.
 
Maybe you have better World Wide Web insurance than I do, but Dr. Internet told me that isopropyl alcohol is slightly more bactericidal against Gram-negative and Gram-positive bacteria (like E. coli and S. aureus) than ethyl alcohol.

And also she said isopropyl alcohol evaporates slightly slower or at a comparable rate depending on concentration, but both require adequate wet time (usually 70% concentration) to denature microbial proteins effectively. The slow tortoise wins.

Were I you, I'd use up the sticks, then switch to @spanky2026's idea, using a bottle of 70% isopropyl alcohol and thoroughly drenching a standard cotton swab
 
spanky2026 said:


I like the idea, though my poor self immediately thought, "Why not just dip a q-tip in alcohol?" Same concept? Cheaper.

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That's what I do. I got a sandwich bag full of Q-tips and alcohol to clean my pens.
 
indolent said:


Maybe you have better World Wide Web insurance than I do, but Dr. Internet told me that isopropyl alcohol is slightly more bactericidal against Gram-negative and Gram-positive bacteria (like E. coli and S. aureus) than ethyl alcohol.

And also she said isopropyl alcohol evaporates slightly slower or at a comparable rate depending on concentration, but both require adequate wet time (usually 70% concentration) to denature microbial proteins effectively. The slow tortoise wins.

Were I you, I'd use up the sticks, then switch to @spanky2026's idea, using a bottle of 70% isopropyl alcohol and thoroughly drenching a standard cotton swab

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We're probably splitting hairs anyway.

NIH says cleaning vials with alcohol doesn't matter anyway, at least for single use vials.

I just feel better doing it...
 
Herkimer P Shagnasty said:


We're probably splitting hairs anyway.

NIH says cleaning vials with alcohol doesn't matter anyway, at least for single use vials.

I just feel better doing it...

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I'm the same way about swabbing injection site skin ... WHO recommends it, CDC doesn't. 1-2¢.
 
indolent said:


I'm the same way about swabbing injection site skin ... WHO recommends it, CDC doesn't. 1-2¢.

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Yea they were cheap enough, maybe 8¢ each. Sterile and individually wrapped, great for travel. I was just surprised to see the ethanol in them. I wonder if anybody's seen ethanol used as a disinfectant in a medical setting.
 
Both are fine for this. WHO injection guidance treats 60–70% isopropyl and ethanol as interchangeable for skin and vial septa — wipe, then let it dry fully before you pierce. Avoid methanol or methylated stuff. The ethanol sticks aren't a downgrade; they're just the other common option.
 
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