BNF for Children 2011-2012

724 Appendix 1: Interactions BNFC 2011–2012Appendix 1: InteractionsQuinine. Antivirals (continued)quinine given with .saquinavir—avoid concomitantuse. Cardiac Glycosides: quinine increases plasma concentrationof .digoxinDopaminergics: quinine possibly increases plasmaconcentration of amantadineHistamine: avoidance of antimalarials advised bymanufacturer of histamineMuscle Relaxants: quinine possibly enhances effects ofsuxamethoniumUlcer-healing Drugs: metabolism of quinine inhibitedby cimetidine (increased plasma concentration)Vaccines: antimalarials inactivate oral typhoidvaccine—see p. 620Quinolones. Analgesics: possible increased risk of convulsionswhen quinolones given with .NSAIDs; manufacturerof ciprofloxacin advises avoid premedication withopioid analgesics (reduced plasma concentration ofciprofloxacin) when ciprofloxacin used for surgicalprophylaxisAntacids: absorption of ciprofloxacin, levofloxacin,moxifloxacin, norfloxacin and ofloxacin reduced byantacids. Anti-arrhythmics: increased risk of ventricular arrhythmiaswhen levofloxacin or moxifloxacin given with.amiodarone—avoid concomitant use; increased riskof ventricular arrhythmias when moxifloxacin givenwith .disopyramide—avoid concomitant use. Antibacterials: increased risk of ventricular arrhythmiaswhen moxifloxacin given with parenteral.erythromycin—avoid concomitant use; effects ofnalidixic acid possibly antagonised by nitrofurantoin. Anticoagulants: ciprofloxacin, nalidixic acid,norfloxacin and ofloxacin enhance anticoagulanteffect of .coumarins; levofloxacin possibly enhancesanticoagulant effect of coumarins and phenindione. Antidepressants: ciprofloxacin inhibits metabolism of.duloxetine—avoid concomitant use; avoidance ofciprofloxacin advised by manufacturer of.agomelatine; increased risk of ventricular arrhythmiaswhen moxifloxacin given with .tricyclics—avoid concomitant useAntidiabetics: norfloxacin possibly enhances effects ofglibenclamideAntiepileptics: ciprofloxacin increases or decreasesplasma concentration of phenytoin. Antihistamines: increased risk of ventricular arrhythmiaswhen moxifloxacin given with .mizolastine—avoid concomitant use. Antimalarials: avoidance of quinolones advised bymanufacturer of .artemether/lumefantrine;increased risk of ventricular arrhythmias whenmoxifloxacin given with .chloroquine and hydroxychloroquine,.mefloquine or .quinine—avoid concomitantuse. Antipsychotics: increased risk of ventricular arrhythmiaswhen moxifloxacin given with .benperidol—manufacturer of benperidol advises avoid concomitantuse; increased risk of ventricular arrhythmiaswhen moxifloxacin given with .droperidol,.haloperidol, .phenothiazines, .pimozide or.zuclopenthixol—avoid concomitant use; ciprofloxacinincreases plasma concentration of clozapine;ciprofloxacin possibly increases plasma concentrationof olanzapine. Atomoxetine: increased risk of ventricular arrhythmiaswhen moxifloxacin given with .atomoxetine. Beta-blockers: increased risk of ventricular arrhythmiaswhen moxifloxacin given with .sotalol—avoidconcomitant useCalcium Salts: absorption of ciprofloxacin reduced bycalcium salts. Ciclosporin: increased risk of nephrotoxicity whenquinolones given with .ciclosporin. Clopidogrel: ciprofloxacin possibly reduces antiplateleteffect of .clopidogrelQuinolones (continued). Cytotoxics: nalidixic acid increases risk of melphalantoxicity; ciprofloxacin possibly reduces excretion ofmethotrexate (increased risk of toxicity); ciprofloxacinincreases plasma concentration of erlotinib;increased risk of ventricular arrhythmias whenlevofloxacin or moxifloxacin given with .arsenictrioxideDairy Products: absorption of ciprofloxacin and norfloxacinreduced by dairy productsDopaminergics: ciprofloxacin increases plasma concentrationof rasagiline; ciprofloxacin inhibitsmetabolism of ropinirole (increased plasma concentration)5HT 1 Agonists: quinolones possibly inhibit metabolismof zolmitriptan (reduce dose of zolmitriptan)Iron: absorption of ciprofloxacin, levofloxacin, moxifloxacin,norfloxacin and ofloxacin reduced by oralironLanthanum: absorption of quinolones possibly reducedby lanthanum (give at least 2 hours before or 4 hoursafter lanthanum). Muscle Relaxants: norfloxacin possibly increasesplasma concentration of tizanidine (increased risk oftoxicity); ciprofloxacin increases plasma concentrationof .tizanidine (increased risk of toxicity)—avoidconcomitant useMycophenolate: norfloxacin possibly reduces bioavailabilityof mycophenolate. Pentamidine Isetionate: increased risk of ventriculararrhythmias when moxifloxacin given with .pentamidineisetionate—avoid concomitant useProbenecid: excretion of ciprofloxacin, nalidixicacid and norfloxacin reduced by probenecid(increased plasma concentration)Sevelamer: bioavailability of ciprofloxacin reduced bysevelamerStrontium Ranelate: absorption of quinolones reducedby strontium ranelate (manufacturer of strontiumranelate advises avoid concomitant use). Theophylline: possible increased risk of convulsionswhen quinolones given with .theophylline;ciprofloxacin and norfloxacin increase plasma concentrationof .theophyllineUlcer-healing Drugs: absorption of ciprofloxacin,levofloxacin, moxifloxacin, norfloxacin and ofloxacinreduced by sucralfateVaccines: antibacterials inactivate oral typhoidvaccine—see p. 620Zinc: absorption of ciprofloxacin, levofloxacin, moxifloxacin,norfloxacin and ofloxacin reduced by zincRabeprazole see Proton Pump InhibitorsRaloxifeneAnticoagulants: raloxifene antagonises anticoagulanteffect of coumarinsLipid-regulating Drugs: absorption of raloxifenereduced by colestyramine (manufacturer of raloxifeneadvises avoid concomitant administration)Raltegravir. Antibacterials: plasma concentration of raltegravirreduced by .rifampicin—consider increasing dose ofraltegravir. Ulcer-healing Drugs: plasma concentration of raltegravirincreased by .omeprazole—avoid concomitantuse; plasma concentration of raltegravir possiblyincreased by histamine H 2 -antagonists and protonpump inhibitors—manufacturer of raltegravir advisesavoid concomitant useRaltitrexed. Antipsychotics: avoid concomitant use of cytotoxicswith .clozapine (increased risk of agranulocytosis). Folates: manufacturer of raltitrexed advises avoidconcomitant use with .folatesRamipril see ACE InhibitorsRanitidine see Histamine H 2 -antagonistsRanolazine. Anti-arrhythmics: manufacturer of ranolazine advisesavoid concomitant use with .disopyramide