Quinolones Quinolone antibacterials Theophylline

The interaction between the quinolone antibacterials and CYP1A2 has been studied in some depth for enoxacin and pefloxacin. Both compounds have been shown to inhibit CYPlA2-mediated metabolism of caffeine in vitro (49). This in vitro inhibition translated into a twofold decrease in caffeine clearance by pefloxacin and a sixfold decrease in clearance by enoxacin (50). Because pefloxacin undergoes N-demethylation to norfloxacin (51) and norfloxacin is much more potent as an inhibitor than pefloxacin (50), the observed in vivo interaction seen for pefloxacin may, in part, be due to norfloxacin. Many other quinolone antibacterial agents have been investigated for their interaction with theophylline, and ciprofloxacin has also been shown to have notable inhibitory effects (52). 

Niki Y, Soejima R, Kawane H, Sumi M, Umeki S. New synthetic quinolone antibacterial agents and serum concentration of theophylline. Cftesf (1987) 92,663-9. 

Sorgel F, Mahr G, Granneman GR, Stephan U, Nickel P, Muth P. Effects of 2 quinolone antibacterials, temafloxacin and enoxacin, on theophylline pharmacokinetics. Clin PAarmacoAinef (1992) 22 (Su pl 1), 65-74. 

In summary, the adverse effects associated with the quinolones appear presently to be mild to moderate in severity and reversible upon discontinuation of therapy. Severe systemic adverse reactions are rare [62], It is suggested that the use of these agents should be avoided, as far as possible, in children and pregnant women and that caution be used in their administration to patients with a seizure disorder or those taking theophylline or warfarin [62]. Articles suggesting the appropriate clinical usage for these important antibacterials have appeared [64],... 

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