A healthy, 23 year old male patient experiences a warm sensation, diaphoresis, nausea, light headedness and then loses consciousness approximately 30 seconds following the injection of 1.8ml of 2% lidocaine with 1:100,000 epinephrine for an inferior alveolar nerve block. What is the most likely diagnosis for his situation?

Syncope

Intravascular injection of local anesthetic

Overdose of local anesthetic

Allergic reaction to local anesthetic