BNF for Children 2011-2012

660 Appendix 1: Interactions BNFC 2011–2012Appendix 1: InteractionsAminoglycosides (continued). Muscle Relaxants: aminoglycosides enhance effects of.non-depolarising muscle relaxants and.suxamethonium. Parasympathomimetics: aminoglycosides antagoniseeffects of .neostigmine and .pyridostigmine. Tacrolimus: increased risk of nephrotoxicity whenaminoglycosides given with .tacrolimusVaccines: antibacterials inactivate oral typhoidvaccine—see p. 620Vitamins: neomycin possibly reduces absorption ofvitamin AAminophylline see TheophyllineAminosalicylatesAzathioprine: possible increased risk of leucopeniawhen aminosalicylates given with azathioprineCardiac Glycosides: sulfasalazine possibly reducesabsorption of digoxinCytotoxics: possible increased risk of leucopenia whenaminosalicylates given with mercaptopurineFolates: sulfasalazine possibly reduces absorption offolic acidAmiodaroneNote Amiodarone has a long half-life; there is a potential fordrug interactions to occur for several weeks (or evenmonths) after treatment with it has been stoppedAgalsidase Alfa and Beta: amiodarone possiblyinhibits effects of agalsidase alfa and beta (manufacturersof agalsidase alfa and beta advise avoidconcomitant use)Anaesthetics, Local: increased myocardial depressionwhen anti-arrhythmics given with bupivacaine, levobupivacaine,prilocaine or ropivacaine. Anti-arrhythmics: increased myocardial depressionwhen anti-arrhythmics given with other .antiarrhythmics;increased risk of ventricular arrhythmiaswhen amiodarone given with .disopyramide or.dronedarone—avoid concomitant use; amiodaroneincreases plasma concentration of .flecainide (halvedose of flecainide). Antibacterials: increased risk of ventricular arrhythmiaswhen amiodarone given with parenteral.erythromycin—avoid concomitant use; increasedrisk of ventricular arrhythmias when amiodaronegiven with .levofloxacin or .moxifloxacin—avoidconcomitant use; possible increased risk of ventriculararrhythmias when amiodarone given withsulfamethoxazole and trimethoprim (as co-trimoxazole)—manufacturerof amiodarone advises avoidconcomitant use of co-trimoxazole. Anticoagulants: amiodarone inhibits metabolism of.coumarins and .phenindione (enhanced anticoagulanteffect); amiodarone increases plasmaconcentration of .dabigatran etexilate (reduce doseof dabigatran etexilate). Antidepressants: increased risk of ventricular arrhythmiaswhen amiodarone given with .tricyclics—avoid concomitant use. Antiepileptics: amiodarone inhibits metabolism of.phenytoin (increased plasma concentration). Antihistamines: increased risk of ventricular arrhythmiaswhen amiodarone given with .mizolastine—avoid concomitant use. Antimalarials: avoidance of amiodarone advised bymanufacturer of .artemether/lumefantrine (risk ofventricular arrhythmias); increased risk of ventriculararrhythmias when amiodarone given with .chloroquineand hydroxychloroquine, .mefloquine or.quinine—avoid concomitant use. Antimuscarinics: increased risk of ventricular arrhythmiaswhen amiodarone given with .tolterodine. Antipsychotics: increased risk of ventricular arrhythmiaswhen anti-arrhythmics that prolong the QTinterval given with .antipsychotics that prolong theQT interval; increased risk of ventricular arrhythmiaswhen amiodarone given with .benperidol—manufacturerof benperidol advises avoid concomitant use;increased risk of ventricular arrhythmias whenamiodarone given with .amisulpride, .droperidol,Amiodarone. Antipsychotics (continued).haloperidol, .phenothiazines, .pimozide or.zuclopenthixol—avoid concomitant use; increasedrisk of ventricular arrhythmias when amiodaronegiven with .sulpiride. Antivirals: plasma concentration of amiodarone possiblyincreased by .atazanavir; plasma concentrationof amiodarone possibly increased by .fosamprenavir(increased risk of ventricular arrhythmias—avoidconcomitant use); plasma concentration of amiodaronepossibly increased by .indinavir—avoid concomitantuse; increased risk of ventriculararrhythmias when amiodarone given with.nelfinavir or .saquinavir—avoid concomitant use;plasma concentration of amiodarone increased by.ritonavir (increased risk of ventricular arrhythmias—avoidconcomitant use). Atomoxetine: increased risk of ventricular arrhythmiaswhen amiodarone given with .atomoxetine. Beta-blockers: increased risk of bradycardia, AV blockand myocardial depression when amiodarone givenwith .beta-blockers; increased myocardial depressionwhen anti-arrhythmics given with .beta-blockers;increased risk of ventricular arrhythmias whenamiodarone given with .sotalol—avoid concomitantuse. Calcium-channel Blockers: increased risk of bradycardia,AV block and myocardial depression whenamiodarone given with .diltiazem or .verapamil. Cardiac Glycosides: amiodarone increases plasmaconcentration of .digoxin (halve dose of digoxin)Ciclosporin: amiodarone possibly increases plasmaconcentration of ciclosporin. Colchicine: amiodarone possibly increases risk of.colchicine toxicity. Cytotoxics: increased risk of ventricular arrhythmiaswhen amiodarone given with .arsenic trioxideDiuretics: increased cardiac toxicity with amiodarone ifhypokalaemia occurs with acetazolamide, loopdiuretics or thiazides and related diuretics; amiodaroneincreases plasma concentration of eplerenone(reduce dose of eplerenone)Grapefruit Juice: plasma concentration of amiodaroneincreased by grapefruit juice. Ivabradine: increased risk of ventricular arrhythmiaswhen amiodarone given with .ivabradine. Lipid-regulating Drugs: increased risk of myopathywhen amiodarone given with .simvastatin. Lithium: manufacturer of amiodarone advises avoidconcomitant use with .lithium (risk of ventriculararrhythmias)Orlistat: plasma concentration of amiodarone possiblyreduced by orlistat. Pentamidine Isetionate: increased risk of ventriculararrhythmias when amiodarone given with .pentamidineisetionate—avoid concomitant useThyroid Hormones: for concomitant use of amiodaroneand thyroid hormones see p. 83Ulcer-healing Drugs: plasma concentration of amiodaroneincreased by cimetidineAmisulpride see AntipsychoticsAmitriptyline see Antidepressants, TricyclicAmlodipine see Calcium-channel BlockersAmoxicillin see PenicillinsAmphotericinNote Close monitoring required with concomitant administrationof nephrotoxic drugs or cytotoxicsAntibacterials: increased risk of nephrotoxicity whenamphotericin given with aminoglycosides or polymyxins;possible increased risk of nephrotoxicitywhen amphotericin given with vancomycinAntifungals: amphotericin reduces renal excretion andincreases cellular uptake of flucytosine (toxicitypossibly increased); effects of amphotericin possiblyantagonised by imidazoles and triazoles; plasmaconcentration of amphotericin possibly increased bymicafungin