To date, no systemic complications associated with Botox injections have been documented. The most common side effects are local numbness, swelling, bruising, or a burning sensation during injection. Lidocaine is used to diminish these side effects and has few adverse reactions. In the case reported here, a 43-year-old woman with a history of chronic pain, muscle spasm, and rigidity of the upper and lower back and neck was evaluated at a clinic and injected with Botox, which produced dramatic improvement within 3 months and lasted for approximately 7 months. Upon returning to the clinic for repeat Botox injections, she was injected at strategic sites on her body with 100 units (1 cc per unit) diluted in 5 cc lidocaine. Upon completion of all the injections, the patient described feeling dizzy and anxious, as well as weakness in the right side of the body. After being transferred to an exam table she had a vaso-vagal reaction and lost consciousness, followed by generalized seizure activity and bladder incontinence. She died after being transferred to an emergency department. The autopsy diagnosed anaphylaxis due to an allergic reaction to the Botox-lidocaine. Despite the reported safety of both drugs, the unpredictability of allergic reactions to drugs administered to a patient for the first time requires that epinephrine and intravenous support be ready to respond to such events. 49 references