GENDER AND AGE AS FACTORS IN THE INHIBITION OF RENAL CLEARANCE OF AMANTADINE BY QUININE AND QUINIDINE

We studied the short-term effect of oral doses of quinine and quinidin e on the renal clearance of amantadine in healthy young (age range, 27 to 39 years) and older (age range, 60 to 72 years) adults of both gen ders in a three-limbed randomized crossover study. Renal clearance of amantadine (3.2 +/- 5.8 L/hr) was significantly inhibited by quinine ( 9.7 +/- 4.8 L/hr) and quinidine (8.9 +/- 4.0 L/hr) only in male subjec ts and was not associated with age. The chiral selectivity for the ren al clearance of quinidine over quinine was confirmed and extended with the suggestion of both age- and gender-associated changes on the rena l clearance ratio for these two diastereomeric drugs. These data suppo rt the continued use of amantadine for studies on the renal eliminatio n of organic cationic drugs.