MDI - use alcohol wipes before every shot?

@CJ114. If I remember correctly (and I’m usually wrong says my wife) alcohol will alter the BG results if there is excess that hasn’t dried. IMHO hand washing is better since it actually cleans your hands (again though, excess water on your fingers will dilute a bg test altering the results).


I haven’t used alcohol wipes for injections for probably 20 years.

I always use alcohol wipes for the Dexcom though because it’s going to be embedded in my body for hopefully 2 weeks or more. There’s a much higher risk of infection. If you were to ever get a pump, using alcohol swabs for insertion sites would be a good idea for similar reasons.


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I use an alcohol swab for my pump sites and Libre/Dexcom sites.

Occasionally use it for injections, but mostly to wipe the top of the pen before putting a needle on. I rarely use one on my skin. I often inject through clothing.

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I think a lot of us on MDI it is also a matter of convenience. I travel to some highly restrictive parts of the world so taking any more than bare minimum requirements becomes a real hassle. We get used to re using needles for weeks on end, injecting through clothing, ditching the swabs and become real good at injecting while, flying, driving, or riding on the back of a donkey cart on a bumpy road. It all becomes about convenience followed by habit.


Never use it, too drying. Nancy50


I use a wipe in the morning, when I take two shots, Toujeo and Humalog. For my other two shots I use a regular cotton ball dipped in alcohol.

Sounds like “regular” means NOT a sterile type of cotton ball, correct?

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And what percentage of alcohol to use if you do? I heard the stronger ones evaporate so fast they aren’t as good. Plus the stronger ones will be very drying to the skin.

" Thank you for contacting the CDC regarding disinfection practices in your practice.

In reference to your first question regarding the recommended concentration for disinfecting surfaces with alcohol, we know that alcohol will denature and coagulate or “fix” proteins. Therefore, alcohol’s antimicrobial properties are best used when the alcohol can make contact with key physiological enzymes and protein structure inside a bacterial cell or fungal cell or virus. Use of the more concentrated solutions (95% or 99%) will result in almost immediate coagulation of surface or cell wall proteins and prevent passage of the alcohol into the cell. The benefits of using 70% alcohol are: 1) coagulation of surface proteins proceeds at a slower pace, thereby allowing the alcohol to enter into the cell; 2) 70% alcohol, being a dilution of absolute alcohol, contains water which is essential in the denaturing process of proteins; and 3) because of concentration difference of water and alcohol on either side of the cell wall, 70% alcohol enters the cell to denature both enzymatic and structural proteins. This increases the potency of its antimicrobial properties. "
So what does this mean? It means that the CDC recommends 70% (up to 91% according to their site) for disinfecting one’s tools or even products because 95% and 99% essentially “freezes” (coagulates) the cell.


I don’t like to use rubbing alcohol because it isn’t just alcohol and water. Rubbing means there are, among other ingredients, lubricants. I like to use 91% alcohol, or just use a BD alcohol wipe, which is what I use 99% of the time I want to use alcohol for a quick skin cleansing.

No. I’m not even sure we have any rubbing alcohol in the house. We have peroxide and neosporin for cut situations.

You are correct, the cotton balls are not sterile. Have been using this method for 40+ years w/out any issues.

I’ve done 3 - 5 injections a day for 37 years without alcohol of any sort and have had no issues at all. Also through clothes many times. No issues.

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It started and stopped inside the week I was at diabetes camp when I was younger. It was routine there. Other than that, I wipe the tops of vials down after I’ve been travelling, but it’s very rare that I bother to.

I rarely used to give shots through clothes. Maybe it’s because I always wore 100% cotton shirts, but little holes could be seen when I started to do it more often. So I stopped unless I was out and about and wanted it to be less noticeable.

Sensor tech if I remember correctly actually creates hydrogen peroxide I think (at least the medtronic ones do) as a chemical reaction that as a side effect cleans the ‘wound’.

No alcohol pads for shots or finger sticks in well over 20 years. I DO wipe my skin thoroughly before Dexcom to help it stick better, though!

I always use alcohol wipes if I haven’t washed my hands. I am 80 years old and I did not know we aren’t supposed to use them LOL!!
I also change the lancet in my fingerstick device, once per week.
I am not in the loop. Must be my age.


I often feel this way too Richard, and you’ve got a couple of decades on me

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I do not use a wipe before insulin injections most of the time. If I am at the gym or playground with kids I do. I do not reuse needles so that may help with no infections cause I have never had one. I always use a wipe on cgm and cgm site. Hope that helps.