Adverse reactions associated with norepinephrine in dental local anesthesia.

Two cases are presented in which a 40-yr-old woman and a 20-yr-old woman developed severe headaches after injection of the local anesthetic Xylestesin-F (3% lidocaine with 1:25,000 norepinephrine). It is suggested that these severe headaches may have been associated with acute transient hypertensive episodes following injection of the local anesthetic. A review of the literature indicates that norepinephrine, at least at a concentration of 1:25,000, should be avoided because of its potential for cardiovascular disturbances.