Accumulation of normeperidine can lead to ________. The risk is higher in patients with ________ and ______ ________.

• A. Sedation; hepatic; renal dysfunction
• B. Seizures; hepatic; renal dysfunction
• C. Hypertension; hepatic disease; renal disease
• D. Drowsiness; hepatic; electrolyte imbalance

Answer: (B)

Normeperidine is a neurotoxic metabolite of meperidine that can accumulate and cause CNS hyperexcitability, leading to seizures. The kidneys mainly clear normeperidine, so renal dysfunction reduces its excretion and lets levels rise. The liver forms normeperidine from meperidine, so hepatic dysfunction can slow clearance and increase formation, further raising risk. When both hepatic and renal function are impaired, accumulation is greatest, making seizures more likely. Sedation or drowsiness can occur, but seizures are the most characteristic and clinically important effect of normeperidine toxicity.