Rarely, a patient presents with a history of being allergic to lidocaine or another kind of local anesthetic. Often, the "allergic" reaction described (racing heart, light-headed, dizziness, etc) is more attributable to the epinephrine which is often used in conjunction with the anesthetic; therefore not a true allergy, but a not unexpected possible side effect. Also, if a true allergy is present, it may not be to the anesthetic itself, but the preservative contained within, typic…