title: Comparative pharmacokinetics of spinal opioids in humans: a step toward determination of relative safety.
mesh_terms: D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000493:pharmacokinetics*; D000767:Anesthesia, Epidural; D000775:Anesthesia, Spinal; D006801:Humans; D008614:Meperidine / Q000008:administration & dosage / Q000493:pharmacokinetics; D009020:Morphine / Q000008:administration & dosage / Q000493:pharmacokinetics; D012449:Safety
chemical_list: D000701:Analgesics, Opioid; D009020:Morphine; D008614:Meperidine