During endodontic access preparation after adequate anesthesia (2 carpules 2% lidocaine 1:100,000 epi + rubber dam), the patient complains of pain. What is the MOST appropriate next step?

With adequate anesthesia confirmed (2 carpules, rubber dam placed), pain during access may indicate inflamed tissue beyond the anesthetic coverage. The best next step is to continue and supplement with intracanal anesthesia (intrapulpal or intraosseous). Antibiotics don't resolve acute pain. Extraction and ER referral are drastic for a manageable situation.