the pharmacokinetics of caffeine , including formation of its major metabolite paraxanthine in plasma , has been investigated in 12 healthy males ( age 20-40 years ) alone and during co-administration of the 4-quinolones ofloxacin , norfloxacin , pipemidic acid , ciprofloxacin , and enoxacin ;
C0034428
quinolones
C0028902
ofloxacin