Isopropyl vs ethanol for disinfection

Herkimer P Shagnasty

Herkimer P Shagnasty

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Before putting on a fresh needle tip, I would always wipe down the cartridge on my injector pen using a disposable isopropyl pad. I had to fold a corner over, cram it in, and twist. I never felt confident about how thoroughly I was actually cleaning it.

After buying some alcohol swabsticks on Amazon, I figured they'd do a better job. They do! Getting to the recessed rubber stopper on the cartridge is far simpler. You snap the stick to let the alcohol out, and done.

What caught me off guard was that they contained ethanol, not isopropyl. Dr. Google says it performs just as well. Does anyone have any input on this?

I've spent time in many clinical environments and have never seen ethanol in use.
 
Seems like a solid approach. I picked some up recently. I was also folding wipes so they'd fit in the tight spot on my pens. Provided the isopropyl alcohol doesn't break down the stopper, it ought to be okay.
 
That approach sounds good, but my first instinct was, "Couldn't I simply soak a cotton swab in alcohol instead?" Isn't that the same thing, only less expensive?
 
Perhaps your access to online information is superior to mine, yet according to what I found on the internet, isopropyl alcohol has a marginally stronger ability to kill both Gram-negative and Gram-positive bacteria (such as E. coli and S. aureus) compared to ethyl alcohol.

Additionally, the same source mentioned that isopropyl alcohol evaporates either a bit more slowly or at a similar speed depending on its concentration, though both types need sufficient wet contact time (typically at 70% concentration) to properly denature microbial proteins. The slower one comes out ahead.

If I were in your position, I would finish using the sticks first, and then adopt the approach suggested by @spanky2026, which involves taking a bottle of 70% isopropyl alcohol and soaking a regular cotton swab thoroughly
 
spanky2026 said:

That approach sounds good, but my first instinct was, "Couldn't I simply soak a cotton swab in alcohol instead?" Isn't that the same thing, only less expensive?
Click to expand...
Same here. My pens get wiped down with Q-tips soaked in alcohol, and I keep a sandwich bag stocked with them.
 
indolent said:

Perhaps your access to online information is superior to mine, yet according to what I found on the internet, isopropyl alcohol has a marginally stronger ability to kill both Gram-negative and Gram-positive bacteria (such as E. coli and S. aureus) compared to ethyl alcohol.

Additionally, the same source mentioned that isopropyl alcohol evaporates either a bit more slowly or at a similar speed depending on its concentration, though both types need sufficient wet contact time (typically at 70% concentration) to properly denature microbial proteins. The slower one comes out ahead.

If I were in your position, I would finish using the sticks first, and then adopt the approach suggested by @spanky2026, which involves taking a bottle of 70% isopropyl alcohol and soaking a regular cotton swab thoroughly
Click to expand...

Honestly, this is likely a distinction without a difference.

According to NIH, wiping down vials with alcohol makes no real difference, at least when they're single-use vials.

Still, it just makes me feel more at ease to do it...
 
Herkimer P Shagnasty said:

indolent said:

Perhaps your access to online information is superior to mine, yet according to what I found on the internet, isopropyl alcohol has a marginally stronger ability to kill both Gram-negative and Gram-positive bacteria (such as E. coli and S. aureus) compared to ethyl alcohol.

Additionally, the same source mentioned that isopropyl alcohol evaporates either a bit more slowly or at a similar speed depending on its concentration, though both types need sufficient wet contact time (typically at 70% concentration) to properly denature microbial proteins. The slower one comes out ahead.

If I were in your position, I would finish using the sticks first, and then adopt the approach suggested by @spanky2026, which involves taking a bottle of 70% isopropyl alcohol and soaking a regular cotton swab thoroughly
Click to expand...

Honestly, this is likely a distinction without a difference.

According to NIH, wiping down vials with alcohol makes no real difference, at least when they're single-use vials.

Still, it just makes me feel more at ease to do it...
Click to expand...
When it comes to wiping down the skin before a shot, I do the same thing ... WHO says to do it, while the CDC does not. It costs 1-2¢.
 
indolent said:

Herkimer P Shagnasty said:

indolent said:

Perhaps your access to online information is superior to mine, yet according to what I found on the internet, isopropyl alcohol has a marginally stronger ability to kill both Gram-negative and Gram-positive bacteria (such as E. coli and S. aureus) compared to ethyl alcohol.

Additionally, the same source mentioned that isopropyl alcohol evaporates either a bit more slowly or at a similar speed depending on its concentration, though both types need sufficient wet contact time (typically at 70% concentration) to properly denature microbial proteins. The slower one comes out ahead.

If I were in your position, I would finish using the sticks first, and then adopt the approach suggested by @spanky2026, which involves taking a bottle of 70% isopropyl alcohol and soaking a regular cotton swab thoroughly
Click to expand...

Honestly, this is likely a distinction without a difference.

According to NIH, wiping down vials with alcohol makes no real difference, at least when they're single-use vials.

Still, it just makes me feel more at ease to do it...
Click to expand...
When it comes to wiping down the skin before a shot, I do the same thing ... WHO says to do it, while the CDC does not. It costs 1-2¢.
Click to expand...
Yeah, the price was low enough — roughly 8¢ apiece. Each one came sterile and sealed on its own, which makes them handy on the go. What caught me off guard was that they contain ethanol. Has anyone here come across ethanol being used to disinfect in a clinical environment?
 
For this purpose, either one works. According to WHO injection guidance, 60–70% isopropyl and ethanol can be used interchangeably on skin and vial septa — wipe, then wait until it has completely dried before piercing. Steer clear of methanol or methylated products. The ethanol sticks aren't inferior; they're simply the other widely used choice.
 
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