What is the maximum dose of lidocaine for a 70 kg adult?

• A. 300 Mg
• B. 250 Mg
• C. 350 Mg
• D. 400 Mg

Answer: (A)

The key idea is using dose per body weight to stay within the safe limit for lidocaine. For lidocaine without a vasoconstrictor, the maximum recommended is about 4.5 mg per kilogram. For a 70 kg adult, that math gives 315 mg, but in practice this is typically rounded down to 300 mg to maintain a safety margin. So the maximum dose is 300 mg. If a vasoconstrictor were used, the limit would be higher (around 7 mg/kg up to ~500 mg), but since the question doesn’t specify a vasoconstrictor, 300 mg is the appropriate ceiling.