What are typical signs of systemic lidocaine toxicity and how is it managed?

• A. CNS signs (tremors, seizures) and CV signs (arrhythmias); management includes stopping the drug and supportive care
• B. GI upset; increase dose
• C. Skin rashes; discontinue use
• D. Hair loss; apply topical ointment

Answer: (A)

Systemic lidocaine toxicity occurs when the drug reaches high enough blood levels to affect both the brain and the heart. The typical signs reflect this: central nervous system involvement such as tremors, restlessness, and seizures, along with cardiovascular problems like arrhythmias, conduction abnormalities, bradycardia, and hypotension. This pattern comes from lidocaine blocking voltage-gated sodium channels in neurons and in cardiac tissue, so you see early CNS excitability and, as levels rise, serious cardiac effects. Management focuses on stopping exposure immediately and providing supportive care: secure the airway and breathing, administer oxygen, monitor the heart, treat seizures with benzodiazepines if they occur, support circulation as needed, and follow advanced toxicity protocols (including lipid emulsion therapy) as indicated. The other options don’t fit because they describe noncharacteristic symptoms (GI upset, skin changes, hair loss) or suggest increasing the dose, which would worsen toxicity.