Expert: Steven C. Scherr, D.D.S. - 12/16/2007

Question
In the past year I have had three restorations. Two on the upper right, and one on the lower left. Each time, I received local anesthesia. After the anesthesia wore off, my sinuses were severely congested for approximately four hours. The congestion occurred only after the numbness subsided. I asked the dentist about it and he wasn't sure. Am I allergic to the lidocaine? If not, what are other
possibilities?


Answer
D.A.

Allergies to lidocaine are extremely rare.  Even if an allergy were present, sinus congestion would not be an expected symptom.

Fluid release from glands in the sinuses is primarily under the control of the parasympathetic nervous system.  I suppose it is possible that some type of parasympathetic stimulation could occur in response to the administration of the anesthetic.  Local anesthetic administered to numb the upper back teeth could potentially diffuse into the sinuses.  However, if the sinuses became congested following both the upper and lower injections, it is not likely to be from the injection or the local anesthetic directly.  This is because the site of the lower injection is well distant from the sinuses and I can envision no known direct pathway of communication.  Possibly body position (laying back for an extended period to have the dental work done) or anxiety (fear of shots) could play a role.

These are just educated guesses.  This is an unusual side effect.  If it resolves within 4 hours, there doesn't seem to be too much to be concerned about.

Best wishes,

Steve