[Diphenhydramine is useful in a parturient with hypersensitivity to local anesthetics to manage her delivery].

We did an obstetric management of a parturient, aged 32 years, with a history of local anesthetic hypersensitivity. The results of histamine release test, and cellular antigen stimulation test with lidocaine, mepivacaine, bupivacaine and preservative-free lidocaine during her pregnancy showed that all local anesthetics studied were positive. We used diphenhydramine as an alternative local anesthetic for episiotomy to the parturient during the delivery. Infiltration with diphenhydramine provided adequate analgesia without noticeable adverse reaction. One month after the delivery, we performed provocative challenge test with local anesthetics, and confirmed she had positive tests to lidocaine, mepivacaine and preservative-free lidocaine, and negative test to bupivacaine. Diphenhydramine is an adequate alternative of local anesthetics in patients with history of hypersensitivity to local anesthetics.