14 doctors weighed in:
Why should a diabetic swab the site of insulin injections with rubbing alcohol first?
14 doctors weighed in

Dr. Susan Wingo
Internal Medicine - Endocrinology
9 doctors agree
In brief: Prevent infection
Bacteria live on the skin surface.
Alcohol kills them so the needle doesn't pick up living bacteria & deliver them under the skin where they can cause an infection (cellulitis). This is the same reason for an alcohol wipe when blood is drawn from an arm vein. Fingersticks do not generally need alcohol wipes, just a soap & water handwash.

In brief: Prevent infection
Bacteria live on the skin surface.
Alcohol kills them so the needle doesn't pick up living bacteria & deliver them under the skin where they can cause an infection (cellulitis). This is the same reason for an alcohol wipe when blood is drawn from an arm vein. Fingersticks do not generally need alcohol wipes, just a soap & water handwash.
Dr. Susan Wingo
Dr. Susan Wingo
Thank
2 comments
Dr. Sahba Ferdowsi
great answer. Wishing you'all the best.
Dr. David Geffner
Actually, it is the preservative and other added substances in the insulin preparation that kills the bacteria. You do not need alcohol before giving yourself a shot of insulin.
Dr. John Leander Po
Internal Medicine - Infectious Disease
3 doctors agree
In brief: Prevent infection.
Skin surface has many different bacteria that typically don't cause infection unless it is introduced into the tissue by the needle of the Insulin injection.
Rubbing alcohol reduces the amount of bacteria at the injection site so as to minimize the risk of infection such as a cellulitis. To be most effective, recommend that you let the alcohol dry before injection (it will also sting a lot less).

In brief: Prevent infection.
Skin surface has many different bacteria that typically don't cause infection unless it is introduced into the tissue by the needle of the Insulin injection.
Rubbing alcohol reduces the amount of bacteria at the injection site so as to minimize the risk of infection such as a cellulitis. To be most effective, recommend that you let the alcohol dry before injection (it will also sting a lot less).
Dr. John Leander Po
Dr. John Leander Po
Thank
Dr. Ariel Zisman
Internal Medicine - Endocrinology
In brief: For cleanliness
It is only to keep the site clean prior to injection.

In brief: For cleanliness
It is only to keep the site clean prior to injection.
Dr. Ariel Zisman
Dr. Ariel Zisman
Thank
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