Novacain Allergy: When I was 10 years old (1960) I passed out and turned gray at the dentist.
The dentist said never to let anyone give me novacaine again. Since then, I have been able to use carbocaine.
Now I am half-finished with a root canal and the endodontist says he can't continue using carbocaine because it doesn't last long enough. He wants to use Xylocaine.
Is there a way I can predict if it will be safe? My mother has a severe allergy to epinephrine - I don't know if that could be a factor in my allergy. ...Visitor from CA
Although not very common, some patients are truly allergic to the epinepherine in local dental anesthetics.
If you had a severe reaction at age 10, turned grey and passed out I'm sure it upset and scared not only you, but the dentist as well. You may have had a bad reaction to the novacaine, but at age 10 you may have been very scared and apprehensive, which predisposed you to passing out!
A true allergic reaction most likely would have caused itching, reddness and swelling. The edema and swelling in the throat can cut off breathing which would require immediate medical intervention. In this case the dentist would have called 911 and started Advanced Cardiac Life Support.
Although you may not be allergic to epinepherine, your mother's allergy to epi. is a concern. To be totally sure that you do not have an epinepherine allergy, an allergist can preform a small skin test for you.
Since you only have a few days before you return to finish your root canal treatment, why take the chance?
The dentist can simply numb the outside of your tooth with a non-epinepherine local and then once he/she has accessed and opened your tooth, any additional numbing can be completed down each canal.
This is called an intra-pulpal injection,and keeps the tooth very numb. Since non-epi anesthetic does not last as long as local that containes epi, you can keep the dentist informed as to when you are starting to feel any discomfort so he can provide more numbing down the roots.
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