TY - JOUR
T1 - Age, sex, and nitrazepam kinetics
T2 - Relation to antipyrine disposition
AU - Greenblatt, David J.
AU - Abernethy, Darrell R.
AU - Locniskar, Ann
AU - Ochs, Hermann R.
AU - Harmatz, Jerold S.
AU - Shader, Richard I.
N1 - Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 1985/12
Y1 - 1985/12
N2 - Forty healthy men and women 19 to 80 years old received a single 10 mg oral dose of the 7-nitro benzodiazepine nitrazepam. Nitrazepam plasma concentrations were measured during the next 72 hours. Among men, the elderly had a larger volume of distribution (Varea) than did younger subjects (1.96 vs. 1.63 L/kg; P < 0.05); because clearance did not change with age (0.84 vs. 0.95 ml/min/kg), the prolonged t 1 2 in elderly men (28 vs. 20 hours; P < 0.01) was a result of the larger Varea. Elderly and young women did not differ in nitrazepam Varea (2.58 vs. 2.55 L/kg), t 1 2 (26 vs. 27 hours), or total clearance (1.19 vs. 1.09 ml/min/kg). The nitrazepam free fraction in plasma (18%x6 to 19% unbound) was not related to age or sex. Among 18 subjects who also received antipyrine, the clearance of nitrazepam and antipyrine were not correlated (r = 0.23). Thus age minimally influences nitrazepam clearance (accomplished mainly by nitroreduction), which in turn is not significantly related to antipyrine oxidizing capacity.
AB - Forty healthy men and women 19 to 80 years old received a single 10 mg oral dose of the 7-nitro benzodiazepine nitrazepam. Nitrazepam plasma concentrations were measured during the next 72 hours. Among men, the elderly had a larger volume of distribution (Varea) than did younger subjects (1.96 vs. 1.63 L/kg; P < 0.05); because clearance did not change with age (0.84 vs. 0.95 ml/min/kg), the prolonged t 1 2 in elderly men (28 vs. 20 hours; P < 0.01) was a result of the larger Varea. Elderly and young women did not differ in nitrazepam Varea (2.58 vs. 2.55 L/kg), t 1 2 (26 vs. 27 hours), or total clearance (1.19 vs. 1.09 ml/min/kg). The nitrazepam free fraction in plasma (18%x6 to 19% unbound) was not related to age or sex. Among 18 subjects who also received antipyrine, the clearance of nitrazepam and antipyrine were not correlated (r = 0.23). Thus age minimally influences nitrazepam clearance (accomplished mainly by nitroreduction), which in turn is not significantly related to antipyrine oxidizing capacity.
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U2 - 10.1038/clpt.1985.248
DO - 10.1038/clpt.1985.248
M3 - Article
C2 - 4064471
AN - SCOPUS:0022337430
SN - 0009-9236
VL - 38
SP - 697
EP - 703
JO - Clinical Pharmacology and Therapeutics
JF - Clinical Pharmacology and Therapeutics
IS - 6
ER -